Peds Flashcards
Craniosynostosis
“Craniosynostosis” is a fancy word for premature fusion o f one or several o f the cranial
sutures. The consequence o f this premature fusion is a weird looking head and face (with
resulting difficulty getting a date to the prom). Besides looking like a gremlin (or a coneheaded
extraterrestrial forced to live as a typical suburban human), these kids can also have
increased intracranial pressure, visual impairment, and deafness.
There are different named types depending on the suture involved - thus it’s worth spending
a moment reviewing the names and locations of the normal sutures.
Metopic suture
Bones Involved: frontal
Fusion direction: front to back
Fusion order: first ( 2-3months)
coronal suture
Bones Involved: frontal and parietal
Fusion direction: lateral to medial
Fusion order: second
lambdoid suture
Bones Involved: parietal and occipital
Fusion direction: lateral to medial
Fusion order: third
sagitaal suture
Bones Involved: parietal
Fusion direction: back to front
Fusion order: fourth
Sutures overview
• Sutures normally have a serrated (saw tooth) contour
• With early closure the suture will lose the serrated appearance - becoming more dense
and sharp. Eventually the suture will disappear completely.
• For the purpose of multiple choice, you should think about synostosis (early closure) as
likely syndromic - and focus your memorizing on this point.
• Having said that, sagittal and unilateral coronal synostosis are typically idiopathic
Metopic Synostosis
trigonocephaly
Eyes are close together (hypotelorism) Ethmoid sinuses underdeveloped Medial part of the orbit slants up Single suture synostosis most frequently associated with cognitive disorders (growth restriction of the frontal lobes)
“Quizzical Eye” appearance
sagittal syostosis
scaphocephaly or Dolichocephalic
Looks like an upside-down boat. Usually the kids have a normal IQ Usually the kids do NOT have hydrocephalus Associated with Marfans (both are tall and skinny).
most common form
coronal synostosis
brachycephaly
Unilateral subtype is more common.
Unilateral type causes the ipsilateral orbit to
elevate, and contralateral frontal bone to
protrude “frontal bossing”
Bilateral form is Rare - should make you think
syndromes (Borat s brother Bilo *).
“HarlequinEye” * if unilateral.
lambdoid synostosis
turricephaly
Tall Cranium (oxycephaly, acrocephaly) See Next Page for Unilateral Discussion
Least
Common
Form
Plagiocephaly
This word basically means “flat.” You will see it used to describe unilateral coronal synostosis as “anterior plagiocephaly You will see it used to describe unilateral lambdoid synostosis as “posterior plagiocephaly. ” The problem is that many people use the word “plagiocephaly” to describe the specific entity of “deformationalplagiocephaly ’’ - which is just benign positional molding, not a pathologic early closure. On the following page, I’ll go into more detail on this. Just know you may be required to read the question writer’s mind when the word is used to differentiate between the benign and pathologic entities.
POSITIONAL
PLAGIOCEPHALY
Infants that sleep on the same side every night develop a flat spot on the preferred dependent area of the head (occipital flattening). Onset: Weeks After Birth Ipsilateral Ear: Anterior Frontal Bossing: Ipsilateral Most common cause of an abnormal skull shape in infant Management is conservative (sleep on the other side for a bit)
LAMBDOID
CRANIOSYNOSTOSIS
I f this is bilateral think underlying Rhombencephalosynapsis Onset: Birth Ipsilateral Ear: Posterior / Inferior Frontal Bossing: Contralateral Rare as Fuck Management is Surgery
THIS vs THAT: Positional Plagiocephaly vs True Unilateral Lambdoid Synostosis
next step
Outside of the jungle (or the year 1987), the
diagnosis of synostosis is going to be made with
CT + 3D. If asked what test to order I would say
CT with 3D recons. Having said that, they could
show you a skull plain film (from 1987) and ask
you to make the diagnosis on that.
If the test writer was feeling particularly cruel
and bitter he/she could show the diagnosis
with ultrasound. In that case, remember that
a normal open suture will appear as an
uninterrupted hypoechoic fibrous gap
between hyperechoic cranial bones (Bright -
Dark - Bright, Bone - Suture - Bone).
Although certain MR gradient sequences can
be used, MRI has traditionally been
considered unreliable in identifying sutures
individually.
THIS vs THAT: Positional Plagiocephaly vs True Unilateral Lambdoid Synostosis
trivia
^or PurPose muP’ple choice, there are numerous random bone buzzwords that are supposed to elicit the reflexive diagnosis NF-l in your brain when you hear / read them. The more common ones include: • Absence / Dysplasia of the Greater Sphenoid Wing, • Tibial Pseudoarthrosis, • Scoliosis, and • Lateral Thoracic Meningocele. I’d like to add "bone defect in the region o f the lambdoid suture ” or the “asterion defect ” to that list of reflex generators. It’s rare and poorly described - therefore potentially high yield.
Clover Leaf Skull Syndrome
• Also referred to as Kleeblattschadei for the purpose of
fucking with you
• Contrary to what the name might imply - this complex
deformity is not associated with an increased ability to hit
green lights, reliably find good parking spots, or win the
lottery. I think that’s because the shape is more 3 leaf clover,
and not 4 leaf. One might assume, a head shaped like a 4 leaf clover
would probably be luckier.
• Instead, this deformity is characterized by enlargement o f the head
with a trilobed configuration, resembling a three-leaved clover.
• Results from premature synostosis o f coronal and lambdoid sutures
(most commonly), but often the sagittal closes as well.
• Hydrocephalus is a common finding.
• Syndromic Associations: Thanatophoric dysplasia, Apert syndrome
(severe), Crouzon syndrome (severe)
Clover Leaf Skull Syndrome
what sutures are closed
All the sutures are
closed
except the metric
and squamosal
Additional Craniosynostosis Syndromes
Most of the time (85%) premature closure is a primary (isolated) event, although
it can occur as the result o f a syndrome (15%). The two syndromes worth having
vague familiarity with are Apert’s and Crouzon’s
Apert’s
- Brachycephaly (usually)
• Fused Fingers (syndactyly) - “sock hand’
Crouzon’s
- Brachycephaly (usually)
- 1 st Arch structures (maxilla and mandible hypoplasia).
- Associated with patent ductus arteriosus and aortic coarctation.
- Short central long bones (humerus, femur) - “rhizomelia”
- Chiari 1 malformations 3: -70% of cases
Convolutional Markings
Normal gyral impressions on the inner table of the skull. You see them primarily during normal rapid brain growth (age 3-7). Usually mild and favors the posterior skull. If you see them along the more anterior skull then you should think about a “copper beaten” skull from the increased intracranial pressure.
Copper Beaten
The same thing as convolutional markings (the normal gyral impressions), just a shit ton more of them. You also see them along the anterior portions of the skull not just the posterior. Think about things that cause increased intracranial pressure. Classic examples: • Craniosynostosis • Obstructive Hydrocephalus
Luckenschadel - “L a c u n a r”
Oval, round, and finger shaped defects (craters) within the inner surface of the skull Different than Copper Beaten in that: (A) They aren’t gyrifonn. (B) They aren’t related to increased ICP. (C) They are usually present at birth. Instead they are the result of defective bone matrix. Classic Association: • Chiari II malformation / Neural Tube Defects.
lytic Skull Lesions
Lytic skull lesions in kids can come from a couple o f different things (LCH, Infection, Mets,
Epidermoid Cysts, Leptomeningeal Cysts, etc…). The two 1 want you to focus on are LCH and
the Leptomeningeal Cyst (which I will discuss later in the chapter).
LCH
(Langerhans Cell Histiocytosis) - Too many fucking dendritic cells - with local invasion. It
is a sorta pseudo malignancy thing. Nobody really understands it…. For the purpose of the exam
think about this as a beveled hole in the skull. The skull is the most common bone involved with
LCH. It is a pure lytic lesion (no sclerotic border). The beveled look is because it favors the
inner table. It can also produce a sequestrum o f intact bone (“button sequestrum).
lytic skull lesions
gamesmanship
If they tell you (or infer) the kid has neuroblastoma
- think about a met.
Parietal Foramina
These paired, mostly round, defects in the
parietal bones represent benign congenital
defects. The underlying cause is a delayed or
incomplete ossification in the underlying
parietal bones.
They can get big and confluent across the
midline. Supposedly, (at least for the big ones -
> 5mm) they are associations with cortical and
venous anomalies.
Wormian Bones
In technical terms, there are a bunch o f extra squiggles around the lambdoid sutures.
“Intrasutural Bones” they call them.
These things are usually idiopathic - however, if
you see more than 10 you should start thinking
syndromes.
Wormian Bones
gamesmanship
< 10 = Idiopathic
> 10 = First think Osteogenesis Imperfecta
> 10 + Absent Clavicle = Cleidocranial Dysostosis
Wormian Bones
Ddx
There is a massive differential, but 1 would just remember these “PORK-CHOP”
Pyknodysostosis Osteogenesis Imperfecta Rickets Kinky Hair Syndrome (Menke s / Fucked Copper Metabolism) Cleidocranial Dysostosis Hypothyroidism / Hypophosphatasia One too many 21 st chromosomes (Downs) Primary Acro-osteolysis (Hajdu-Cheney)
Dermoid / Epidermoid of the Skull
In the context of the skull, you can think about these things as occurring from the congenital misplacement of cells from the scalp into the bony calvarium. The result is a growing lump o f tissue (keratin debris, skin glands, etc...) creating a bone defect with benign appearing sclerotic borders. There are a few differences between the two subtypes that could be potentially testable (contrasted masterfully in the chart).
Although, I suspect a “what is it ? ” type question is more likely. As such, look through some google image examples to prepare yourself for that contingency.
Epidermoid
Histology:Only Skin
(Squamous
Epithelium)
Age of onset:Present between
age 20-40
Location: Present between
age 20-40
CT: CSF Density
MRI:T1 Variable,
T2 Bright,
NO Enhancement
Dermoid
Histology: Skin + Other Stuff
Like Hair Follicles,
Sweat Glands Etc
Age of onset:Typically have an
earlier presentation
Location: end to be midline.
The skin ones tend to
he around the orbits.
Associated with
Encephaloceles -
especially when
midline
CT: - More Heterogeneous,
- Calcifications
(internal or peripheral)
may be present
MRI: T2 Bright,
+/- Wall Enhancement
Congenital Dermal Sinus
Usually when people talk about these things they are referring to the spina bifida style
midline lumbosacral region defects. However, we are going to stay focused on the skull /
face. The two classic locations for dermal communications with the dura are the occiput and
the nose. Both of which are classically midline, and can be associated with a dermoid cyst.
For gamesmanship, consider a sinus tract anytime you see a cyst in these locations.
Dural communication will require
communication through the foramen cecum.
Sinus tracts may or may not have associated dennal or intraosseous cysts. Cysts may or may not have sinus tracts
THIS vs THAT: Scalp Trauma
There are 3 scalp hematoma subtypes. Because the subtypes are fairly similar, there is a high
likelihood a sadistic multiple choice writer will attempt to confuse you on the subtle
differences
Subgaleal Hemorrhage
Location:Deep to the Aponeurosis
(between aponeurosis and
periosteum)
Suture:NOT limited by
suture lines
Trivia: Covers a much larger area
than a cephalohematoma
Complications:Potentially life-threatening
- rapid blood loss.
Often not seen until 12-72
hours post delivery.
Cause: vacuum extraction
Cephalohematoma
Location: Under the Periosteum
(skin o f the bone)
Suture: Limited by suture lines
(won i cross sutures)
Trivia:Outer border may calcify as a rim
and leave a deformity - sorta like
a myositis ossificans
Complications:Usually requires no intervention (resolves within a few weeks) Can get super infected (E.Coli). Abscess would require drainage. Can cause skull osteomyelitis
Cause:Instrument or Vacuum Extraction
Caput Succedaneum
Location:Subcutaneous
Hemorrhage
(superficial to
the aponeurosis)
Suture:NOT limited by
suture lines
Trivia:Requires no
intervention
(resolves within
a few days)
Cause: prolonged delivery
Skull Fractures
Accidental (and non-accidental) head trauma is supposedly (allegedly, allegedly) the most common
cause of morbidity and mortality in children. As you might imagine, the pediatric skull can fracture
just like the adult skull - with linear and comminuted patterns. For the purpose of multiple choice, I
think we should focus on the fracture patterns that are more unique to the pediatric population:
Diastatic, Depressed, and “Ping-Pong”
Diastatic Fracture
This is a fracture along / involving the suture. When they intersect it is usually
fairly obvious. It can get tricky when the fracture is confined to the suture itself. The most common
victim of this sneaky fracture is usually the Lambdoid, followed by the Resident reading the case on
night float .. .with Attending backup (asleep in bed). How does one know there is traumatic injury to
a suture ? Classically, it will widen. This is most likely to be shown in the axial or coronal plane so
you can appreciate the asymmetry ( > 1 mm asymmetry relative to the other side).
Depressed Fracture
This is a fracture with inward displacement of the bone. How much inward
displacement do you need to call it “depressed” ? Most people will say “equal or greater to the
thickness of the skull.” Some people will use the word “compound” to describe a depressed
fracture that also has an associated scalp laceration. Those same people may (or may not) add the
word “penetrating” to describe a compound fracture with an associated dural tear.
Will any o f those people be writing the questions ? The dark side clouds everything. Impossible to
see the future is.
Ping Pong Fracture
outcomes
Ping Pong fractures typically have a favorable / benign clinical outcome
(depressed fractures have high morbidity).
Ping Pong Fracture
etiology
Diastatic and depressed fracture types usually require a significant wack on
the head. Where as “ping pong” fractures often occur in the setting of birth trauma
(Mom’s pelvic bones +/- forceps).
Ping Pong Fracture
imaging appearnce
Ping Pong fractures are hard as fuck to see. To show this on a
test you’d have to have CT 3D recons demonstrating a smooth inward deformity. You
could never see that shit on a plain film. I can’t imagine anyone being a big enough
asshole to ask you to do that. Hmmm…. probably.
Ping Pong Fracture
This is actually another subtype of depressed fracture but is unique in that it is
a greenstick or “buckle” type of fracture.
NEXT STEP
Depressed Fx
Unlike linear fractures (which usually heal without complication),
depressed fractures often require surgery. Some general indications Fracture
for surgery would include:
Depression of the fragments > 5mm (supposedly fragments more
than 5mm below the inner table are associated with dural tears),
Epidural bleed
Superinfection (abscess, osteomyelitis)
“Form” (cosmetic correction to avoid looking like a gargoyle),
“Function” (if the frontal sinus is involved, sometimes they need
to obliterate the thing to avoid mucocele formation).
Non-Accidental Trauma t Abusive Head Trauma)
Although car wrecks and falls account for the majority o f skull fractures in children, there still remains the timeless truth — some people just can’t take screaming kids. For the purpose of multiple choice, the follow clues should make your spider-sense tingle. • Inconsistent History: “My 7 month old wrecked his bike ” • Subdural Hematoma • Retinal hemorrhage • DAI / Parenchymal Contusion • Cerebral Edema, Stroke (less specific but still worrisome) • Depressed Skull Fx, or Fracture Crossing Suture Line (less specific but still worrisome)
Non-Accidental Trauma t Abusive Head Trauma)
gamesmansship
Subdurals have a stronger association with NAT
relative to epidurals. Think about vigorous
shaking (trying to get that last drop of ketchup
out of the bottle) tearing bridging cortical veins.
“Look High, Look Low”
- Sneaky Ways to Suggest NAT -
- Look High: Thrombosed (hyperdense)
cortical vein at the vertex
- Look Low: Retroclival hematoma (thin
hyperdense sliver in the pre-pontine region)
- Look Lower: Edema within the cervical soft
tissues
THIS VS THAT:
Retroclival Hematoma
Epidural
Below the Tectorial
Membrane
Subdural
Above the tectorial Membrane
THIS vs THAT:
Extra Axial Fluid
Chronic Subdural
(CSF Density)
Medial Displacement
of Bridging Vein
(sometimes smashed and
not well seen).
Usually Unilateral.
If Bilateral Usually
Asymmetric in Size.
Prominent CSF Spaces
Cortical veins are
adjacent to the inner table
Usually Symmetric
Enlarged extra-axial fluid spaces
Extra-axial fluid spaces are considered enlarged if they are
greater than 5 mm. BESSI is the name people throw around
for “benign enlargement of the subarachnoid space in infancy.’
The etiology is supposed to be immature villa (that’s why you
grow out of it).
THIS vs THAT:
BESSI vs Subdural Hygroma
BESSI - Cortical veins are adjacent to the inner table - they are usually seen secondary to enlargement o f the subarachnoid spaces (positive cortical vein sign) Subdural - Cortical veins are displaced away from the inner table - they are often not se
BESSI Trivia:
• It’s the most common cause of macrocephaly,
• Typically presents around month 2 or 3, and has a strong
male predominance.
• Typically resolves after 2 years with no
treatment,
• There is an increased risk of subdural bleed -
either spontaneous or with a minor trauma. This
subdural is usually isolated (all the same blood
age), which helps differentiate it from nonaccidental
trauma, where the bleeds are often of
different ages.
Enlarged extra-axial fluid spaces
trivia
Pre-mature kids getting tortured on ECMO often get enlarged extra-axial spaces. This isn’t really the same thing as BESSI but rather more related to fluid changes / stress.
Bessi imaging
Enlarged symmetric subarachnoid spaces favoring the anterior aspect o f the brain (spaces along the posterior aspect o f the brain are typically normal).
Brain parenchyma is normal and there is either normal ventricle size or very mild
communicating hydrocephalus. Communicating meaning that all 4 ventricles are big.
Periventricular leukomalacia I Hypoxic-Ischemic Encephalopathy of the Newborn
overview
This is the result of an ischemic / hemorrhagic injury, typically from a hypoxic insult during
birthing. The kids who are at the greatest risk are premature and little (less than 1500 g). The
testable stigmata is cerebral palsy - which supposedly develops in 50%. The pathology favors
the watershed areas (characteristically the white matter dorsal and lateral to the lateral
ventricles).
Periventricular leukomalacia I Hypoxic-Ischemic Encephalopathy of the Newborn
The milder finding can be very subtle. Here are some tricks:
The milder finding can be very subtle. Here are some tricks:
(1) Use PreTest Probability: The kid is described as premature or low birth weight.
(2) Brighter than the Choroid: The choroid plexus is an excellent internal control. The
normal white matter should always be less bright (less hyperechoic) when compared to the choroid
(3) “Blush” and “Flaring” : These are two potential distractors that need to be differentiated
from legit grade 1 PVL. “Blush ” describes the physiologic brightness of the
posterosuperior periventricular white matter - this should be less bright than choroid, and
have a more symmetric look. “Flaring” is similar to blush, but a more hedgy term. It’s the
word you use if you aren’t sure if it’s real PVL or just the normal brightness often seen in
premature infants white matter. The distinction is that “flaring” should go away in a
week. Grade 1 PVL persists > 7 days.
Periventricular leukomalacia I Hypoxic-Ischemic Encephalopathy of the Newborn
quick
Early: P e riv en tric u la r W h ite M a tte r N e c ro sis
(hyperechoic relative to choroid)
S u b acu te: C y s t F o rm a tio n
Periventricular leukomalacia I Hypoxic-Ischemic Encephalopathy of the Newborn
trivia
The most severe grade (4), which has subcortical cysts, is actually more common in
full term infants rather than preterms.
Periventricular leukomalacia I Hypoxic-Ischemic Encephalopathy of the Newborn
The later findings are more obvious with the development of cavitary periventricular cysts.
The degree of severity is described by the size and distribution of these cysts. These things take
a while to develop - some people say up to 4 weeks. So, if they show you a day 1 newborn
with cystic PVL they are leading you to conclude that the vascular insult occurred at least 2
weeks prior to birth (not during birth - which is often the case).
Germinal Matrix Hemorrhage ( GMH)
I like to think about the germinal matrix as an embryologic seed that sprouts out various
development cells during brain development. Just like a seed needs water to grow, the
germinal matrix is highly vascular. It’s also very friably and susceptible to stress.
Additionally, premature brains suck at cerebral blood flow auto-regulation. Mechanism:
Fragile vessels + too much pressure/flow = bleeds
An important thing to understand is that the germinal matrix is an embryological entity. So it
only exists in premature infants. As the fetus matures the thing regresses and disappears.
By 32 weeks, germinal matrix is only present at the caudothalamic groove.
By 36 weeks, you basically can’t have it (if no GM, then no GM hemorrhage).
Germinal Matrix Hemorrhage ( GMH)
Take home point
No GM Hemorrhage in a full term infant.
Germinal Matrix Hemorrhage ( GMH)
Gamesmanship
Similar looking bleed in a full term infant say “choroid plexus
hemorrhage” (not GMH).
Germinal Matrix Hemorrhage ( GMH)
scenario
The scenario will always call the kid a premature infant (probably earlier than 30 weeks). The
earlier they are bom the more common it is. Up to 40% occur in the first 5 hours, and most
have occurred by day 4 (90%). A good thing to remember is that 90% occur in the first week.
Germinal Matrix Hemorrhage ( GMH)
screening
Head US is used to screen for this pathology. Testable trivia includes:
• Who should be screened? Premature Infants (<32 weeks, < 1500 grams), Premature Infants
with Lethargy, Seizures, Decreased Hematocrit or a history o f “he don’t look so good.”
• When do you do the head US? First week o f life (remember this is when 90% o f them occur).
Some people will tell you - “first week and first month” (but that varies from institution).
Some people will also say - “every kid gets a head US prior to discharge from the NICU” - but
that is mainly done to detect PVL (not necessarily GMH).
Germinal Matrix Vs Choroid Plexus
Choroid Plexus is bright (hyperechoic) on ultrasound. Blood is also bright (hyperechoic).
You tell them apart based on their location. Choroid should not extend anterior to the junction o f the caudate and the thalamus (the so called caudothalamic groove).
This is the location o f the germinal matrix.
If you see bright stuff there - that is your grade 1 bleed.
This could also be shown with MR1 (T1 bright = bleed), same location.
Germinal Matrix Hemorrhage ( GMH)
Grading System (1-4) -
1 - Blood at the caudothalamic groove 2 - Blood in the ventricles but no dilation. 3 - Blood in the ventricles with dilation 4 - Blood in the brain parenchyma (from venous infarct)
Few additional things you should see at least once
prior to the exam. Do yourself a favor and
google images o f the following
- Caudothalamic groove in the coronal plane
- Grade 2,3,4 Bleeds
- Subependymal Cysts on US
- Porencephalic Cysts on US
- Choroid Plexus Cysts on US
- Ventricular coarctation on US - this is a mimic
Secondary Consequences GMH
Grade 1
Subependymal hemorrhage either results in a subependymal cyst or resolution or to a grade 2
Secondary Consequences GMH
Grade 2/3
Intraventricular hemorrhage results in hydrocephalus or grade 4
Secondary Consequences GMH
Grade 4
intraparenchymal hemorrhage either goes to a porencephalic cyst or hydrocephalus.
Choanal Atresia
Results from a membrane that separates the nasal cavity from its normal communication with the oral cavity. It is
usually unilateral but can be bilateral. The bilateral ones have a history
of “cyclical cyanosis that improves with crying ” (they mouth breath
when they cry). The unilateral classic stories are “can’t pass NG
tube, ” and “respiratory distress while feeding” (neonates have to
breath through their noses). You will also sometimes hear a history of
“a continuous stream o f snot draining from one or both nostrils, ” or
the word “rhinorrhea. ”
Choanal Atresia
types
There are two different types: bony (90%), and
membranous (10%). The appearance is a
unilateral or bilateral posterior nasal narrowing,
with thickening of the vomer.
Choanal Atresia
trivia
There are many syndromic associations
including CHARGE. Crouzons, DiGeorge,
Treacher Collins, and Fetal Alcohol Syndrome.
CHARGE is the one people mention the most.
CHARGE
Coloboma, Heart defect, Atresia (Choanal) Retarded growth, Genitourinary abnormalities Ear anomalies
Congenital Piriform Aperture Stenosis
This results from abnormal development of the medial nasal eminences,
and subsequent failure of formation of the primary palate. You can
see this in isolation or with choanal atresia. The piriform aperture of
the nasal cavity (bony inlet of the nose) is stenotic (as the name
suggests), and the palate is narrow. The classic picture is the
associated central maxillary “MEGA-incisor.” Midlinc defects
of the brain (corpus callosum agenesis, and holoprosencephaly) are
associated
— as my Grandma always said “face predicts brain ”.
Congenital Piriform Aperture Stenosis
next step
You have to image the brain
Congenital Piriform Aperture Stenosis
big thing to know
The big thing to know is the high association with hypothalamicpituitary-
adrenal axis dysfunction.
Ectopic Thyroid
Thyroid topics will be covered again in the endocrine chapter. 1 do want to mention one or two now for
completeness. To understand ectopic thyroid trivia you need to remember that the thyroid starts
(embryology wise) at the back of the tongue. It then descends downward to a location that would be
considered normal. The “pyramidal lobe” actually represents a persistence of the inferior portion of the
thyroglossal duct - that is why this thing is so variable in appearance. Sometimes this process gets all
fucked up and the thyroid either stays at the back of the tongue (lingual thyroid) or ends up half way
down the neck or even in the chest (ectopic thyroid).
Ectopic Thyroid
trivia to know
- Most “developed” countries test for low thyroid at birth (Guthrie Test). That will trigger a workup for either ectopic tissue or enzyme deficiencies.
- Nukes (1-123 or Tc-MIBI) is superior to ultrasound for diagnosing ectopic tissue. This is by far the most likely way to show this on a multiple choice exam. I guess CT would be #2 - remember thyroid tissue is dense because of the iodine.
- Ultrasound does have a preoperative role in any MIDLINE neck mass - with the point of ultrasound being to confirm that you have a normal thyroid in a normal place. If you resect a midline mass (which turns out to be the kids only thyroid tissue) you can expect an expensive well rehearsed didactic lecture on pediatric neck pathology from an “Expert Witness” sporting a $500 haircut.
- Lingual thyroid (back of the tongue) is the most common location of ectopic thyroid tissue
Thyroglossal Duct Cyst
As we discussed previously, thyroid related pathology can occur
anywhere between the foramen cecum (the base of the tongue)
and the thyroid gland. In this situation we are talking about the
duct (which is the embryological thyroid interstate highway to the
neck) failing to involute fully. What you get is a left over cyst -
hence the name. The classic locations are (1) at the base of the
tongue, and (2) midline anterior to the hyoid. Now textbooks will
make a big deal about these things becoming slightly lateral below
the hyoid. Do NOT get hung up on that. For the purpose of multiple
choice remember these guys are midline. Midline is the buzzword.
Thyroglossal Duct Cyst
things to know
- Classic Buzzword / Scenario = Midline Cyst in the Neck o f a Kid.
- Next step once you find one = confirm normal thyroid location and/or look for ectopic tissue (Ultrasound +/-Tc-M1BI, or 1-123).
- They are cystic (it’s not called a “Duct Solid”)
- Enhancing nodule within the cyst = CANCER (usually papillary)
- They can get infected.
Dermoid Cyst
It is true that dermoids almost always occur below the clavicles, but
when they do happen in the neck they have a pretty classic look:
midline sublingual / submandibular space with a “sac of marbles”
appearance. The marbles are lobules of fat within fluid.
Branchial Cleft Cyst (BCC)
Another cystic embryologic remnant. There are a bunch o f types (and subtypes… and subsubtypes)
and you can lose your fucking mind trying to remember all o f them - don’t do that.
Just remember that by far the most common is a 2nd Branchial Cleft Cyst (95%). The angle
of the mandible is a classic location. They can get infected, but are often asymptomatic.
Extension o f the cyst between the ICA and ECA (notch sign) just above the carotid
bifurcation is pathognomonic.
Branchial Cleft Cyst (BCC)
what is it
Most likely on CT or MR1. Ultrasound would be tough, unless they clearly
labeled the area “lateral neck” or oriented you in some other way.
Branchial Cleft Cyst (BCC)
location
They could (and this would be super mean) ask you the relationship o f a type 2 based on other neck anatomy. So - posterior and lateral to the submandibular gland or lateral to the carotid space, or anterior to the sternocleidomastoid. How I would handle that? Just remember it’s going to be lateral to everything. Lateral is the buzzword
Branchial Cleft Cyst (BCC)
mimic
They could try and trick you into calling a necrotic level 2 lymph node a BCC. Thyroid cancer (history o f radiation exposure) and nasopharyngeal cancer (history ofHPV) can occur in “early adulthood.” If you have a “new” BCC in an 18 year old - it’s probably a necrotic node. Next Step = Find the cancer +/- biopsy the mother fucker.
I say LATERAL
cyst in the neck,
you say
branchial cleft cyst
1 say MIDLINE
cyst in the neck,
you say
thyroglossal duct cyst
Jugular Vein Pathology
Septic Thrombophlebitis
clotted jugular vein. You see this classically in the setting of a
recent pharyngeal infection (or recent ENT surgery).
Jugular Vein Pathology
Septic Thrombophlebitis
what is it
Showing the clotted vein with the appropriate clinical history.
Jugular Vein Pathology
Septic Thrombophlebitis
“Lemierre’s Syndrome”
Seeing if you know that it has a fancy syndrome name.
Jugular Vein Pathology
Septic Thrombophlebitis
Next Step
Looking in the lungs for septic emboli. This could also be done in the reverse. Show
you the septic emboli, give you a history of ENT procedure (or recent infection), and have you ask
for the US of the neck veins.
Jugular Vein Pathology
Septic Thrombophlebitis
USMLE Step I Association Trivia
Fusobacterium necrophorum is the bacteria that causes the
septic emboli. As this bacteria sounds like a Marvel Comic villain the likelihood of it being asked
increases by at least 5x.
Jugular Vein Pathology
Phlebectasia
Idiopathic dilated jugular vein.
Jugular Vein Pathology
Phlebectasia
What is it
showing the dilated vein
Jugular Vein Pathology
Phlebectasia
trivia 1
is it not related to a stenosis. there aren o other signs of venous congestion
Jugular Vein Pathology
Phlebectasia
trivia 2
It gets worse with the Valsalva maneuver - “neck mass that enlarges with valsalva. ”
Both lymphatic and venous malformations can both look like a large transspatial
multicystic mass in the neck. They can both have fluid levels.
If you must try and tell them apart - you could try this:
• Venous Malformations will have enhancement of the cystic spaces.
• Lymphatic Malformations will have enhancement of the septa.
• Phlcboliths — suggests venous.
Hemangioma of Infancy
These things are actually the most common congenital lesions in the head and neck. Just like
any hemangioma they contain vascular spaces with varying sizes and shapes. Most people
consider them a “tumor” more than a vascular malformation.
Hemangioma of Infancy
how they look
Super T2 bright, with a bunch of
flow voids. Diffusely vascular on doppler.
Hemangioma of Infancy
phases
Typically they show up around 6 months of age, grow for a bit, then plateau, then involute (6-10 years). Usually they require no treatment.
Hemangioma of Infancy
indications for treatment
Large size / Rapid growth
with mass effect on the airway or adjacent vascular structures. Fucking with the kids eye movement or eyelid opening.
Hemangioma of Infancy
treatment
Typically medical = Beta blocker
propranolol
Hemangioma of Infancy
associations
PHACES Syndrome (discussed later in the chapter)
Cystic Hygroma (Lymphangioma)
This is another cystic lesion o f the neck, which is most likely to be shown as an OB
ultrasound (but can occur in the Peds setting as well). The classic look / location is a cystic
mass hanging off the back o f the neck on OB US (or in the posterior triangle if CT/MR1).
Cystic Hygroma (Lymphangioma)
associations
Turners (most common association).
Downs (second most common association).
Aortic Coarctation (most common CV abnormality), Fetal Hydrops (bad bad bad outcomes).
Cystic Hygroma (Lymphangioma)
septations
worse outcome
Cystic Hygroma (Lymphangioma) t2
T2 Bright (like a hemangioma). Does NOT enhance (hemangiomas typically do).
Fibromatosis Coli (“Congenital Torticollis”)
overview
This is a benign “mass” of the sternocleidomastoid
in neonates who present with torticollis (chin points
towards the opposite side - or you could say they
look away from the lesion). It’s really just a benign
inflammation that makes the muscle look crazy big.
Ultrasound can look scary, until you realize it’s just
the enlarged SCM. Ultrasound is still the best
imaging test. Sometimes it looks like there are two
of them, but that’s because the SCM has two heads.
It goes away on its own, sometimes they do passive
physical therapy or try and botox them.
Fibromatosis Coli (“Congenital Torticollis”)
trivia
• Most common cause of a neck “mass” in infancy
• Classic scenario is a 4 week old with a palpable neck mass and torticollis toward the affected side
• Best imaging test = US.
• Things that make you think it’s not FC: mass is outside the SCM, or internal calcifications - in
which case you should think to yourself… nice try Mother fuckers- that’s a neuroblastoma.
Fibromatosis Coli (“Congenital Torticollis”)
gamesmanship
So… there can be significant fuckery with the “direction” things curve or people look depending
on how the question is ask. What do I mean ?
If you made the mistake of just memorizing the word “towards” in association with fibromatosis
coli you might get tricked if the options were: A - Patient looks towards the involved side.
B - Patient looks toward the uninvolved side. You’d run into the same problem with the word
“away.”
Now, that might seem obvious once I spell it out like that but I’m pretty sure at least a few of you
were making a flashcard that had only the word “towards” on it. You have to assume the test
writer has the worst intentions for you. Don’t provide them with any opportunity to trick you.
Rhabdomyosarcoma
Although technically rare as fuck, this is the most common mass in the masticator space of a kid.
Having said that if you see it in the head/neck region is almost always in the orbit. In fact, its the most
common extra-occular orbital malignancy in children (dermoid is most common benign orbital mass
in child). The most classic scenario would be an 8 year old with painless proptosis and no signs of
infection.
What do sarcomas look like?
I’ll talk about this more in the MSK chapter, but in general I’ll just say they look mean as cat shit
(enhancing, solid, areas of necrosis, etc..).
Croup
This is the most common cause o f acute upper airway obstruction in young children. The
peak incidence is between 6 months and 3 years (average 1 year). They have a barky
“croupy” cough. It’s viral. The thing to realize is that the lateral and frontal neck x-ray is
done not to diagnosis croup, but to exclude something else. Having said that, the so-called
“steeple sign ” - with loss o f the normal lateral convexities o f the subglottic trachea is your
buzzword, and if it’s shown, that will be the finding. Questions are still more likely to center
around facts (age and etiology).
Croup
culprit
The culprit is often parainfluenza virus.
Epiglottitis
In contrast to the self-limited croup, this one can kill you. It’s mediated by H. Influenza and
the classic age is 3.5 years old (there is a recent increase in teenagers - so don’t be fooled by
that age). The lateral x-ray will show marked swelling o f the epiglottis (thumb sign). A fake
out is the “omega epiglottis” which is caused by oblique imaging. You can look for thickening
o f the aryepiglottic folds to distinguish.
Epiglottitis
trivia
Death by asphyxiation is from the aryepiglotic folds (not the epiglottis)
Exudative Tracheitis (Bacterial Tracheitis)
This is an uncommon but serious (possibly deadly) situation that is found in slightly older
kids. It’s caused by an exudative infection o f the trachea (sorta like diptheria). It’s usually
from Staph A. and affects kids between 6-10.
Exudative Tracheitis (Bacterial Tracheitis)
buzzword
linear soft tissue filling defect
within the airway.
Croup
quick
6 months - 3 years
(peak 1 year)
Steeple Sign: loss o f the normal
shoulders (lateral convexities) of
the subglottic trachea
Viral
(Most Common - parainfluenza)
epiglottitis quick
Classic = 3.5 years, but now
seen with teenagers too
Thumb Sign: marked
enlargement o f epiglottis
h. flu
Exudative tracheitis quick
6-10 years
Linear soft tissue filling
defect (a membrane) seen
within the airway
Staph A
Retropharyngeal Cellulitis and Abscess
I’ll just say quickly that you do see this
most commonly in young kids (age 6 months -12 months). If they don’t show it on CT, they
could show it with a lateral x-ray demonstrating massive retropharyngeal soft tissue
thickening. For the real world, you can get pseudothickcning when the neck is not truly lateral
To tell the difference between positioning and the real thing, a repeat with an extended neck is
the next step.
Subglottic Hemangioma
Hemangiomas are the most common soft tissue mass in the
trachea, and they are most commonly located in the subglott
region. In croup there is symmetric narrowing with loss of
shoulders on both sides (Steeple Sign). In contradistinction,
subglottic hemangiomas have loss of just one o f the sides.
Subglottic Hemangioma
Trivia
- Tends to favor the left side
- 50% are associated with cutaneous hemangiomas
- 7% have the PHACES syndrome
PHACES
P- Posterior fossa (Dandy Walker) H- Hemangiomas A- Arterial anomalies C- Coarctation o f aorta, cardiac defects E- Eye abnormalities S- Subglottic hemangiomas
Laryngeal Cleft
This is a zebra. The classic scenario is contrast appearing in the tracheal without laryngeal penetration
(aspiration). They could also show you a “thin tract of contrast extending to the larynx or trachea.” This
entity is a communicating defect in the posterior wall of the larynx and the esophagus or anterior hypo
pharynx. There arc a bunch of different cleft classifications - 1 can’t imagine that shit is appropriate for
the exam.
Laryngeal Cleft
trivia
• This is a thing - maybe google a Fluoro swallow picture of it
• These things have other complex malformations associated with them (usually GI)
• It is very tricky to call it with certainty on a swallow exam - definite diagnosis is always made with
direct visualization / scope (so a next step type question would recommend endoscopy to confirm).
airway papilloma
If you see a lobulated grape looking thing in the airway - think Papilloma, especially if the lungs are full of nodules (solid and cavitated). When 1 say Papilloma, You say HPV - typically from
perinatal (birth canal) transmission. These things are usually multiple (papillomatosis) and therefore have
multiple areas of airspace disease (atelectasis ect.). Some potential gamesmanship — because these thing
are typically multiple you will have more areas of air trapping then you would compared with an
aspirated crayon (or green bean), or even a solitary endobronchial lesion like a carcinoid. Multiple areas
of air trapping - think Papillomatosis over carcinoid or a foreign body. Having said that the nodules are a
more common finding… lots of them.
- G am e sm a n s h ip -
F ro n ta l an d L a te ra l N e c k R a d io g ra p h s
For the frontal, there are
two main things to think
about.
(1) Croup and
(2) Subglottic
Hemangioma
You can tell them apart
by the shouldering.
If you can’t tell…. try
and let the history bias
you. Cough? Fever?
Think Croup.
- G am e sm a n s h ip -
F ro n ta l an d L a te ra l N e c k R a d io g ra p h s
For the lateral, there are 4 main things to think about:
epiglottitis
retropharygeal abscess
tonsis (adenoids)
exudative tracheitis
lateral radiograph
epiglottitis
Looks like a
thumb
If the ordering suspects the diagnosis, do NOT bring this kid to x-ray. Have them do a portable.
lateral radiograph
retropharyngeal abscess
Too wide ( > 6mm at C2, or > 22mm at C6) Next Step = CT don't forget to look in the mediastinum for “Danger Zone” extension.
lateral radiograph
tonsils (adenoids)
Not seen till about
3-6 months, and not
big till around 1-2
years.
Too big when they
encroach the airway
lateral radiograph
exudative tracheitis
Linear Filling
Defect
It’s usually staph
Know how to tell if a neonatal chest is hyper-inflated or not. Don’t get hung up on this
low vs normal - that’s a bunch o f bologna. Just think (a) Hyper-inflated, or (b) NOT
Hyper-inflated.
The easiest way to do this is to just count ribs. More than 6 Anterior, or 8 Posterior as they intersect the diaphragm is too much. As a quick review, remember that the anterior ribs (grey) are the ones with a more sloping course as they move medially, where as the posterior ribs (black) have a horizontal course.
Other helpful signs suggesting
hyperinflation:
- Flattening o f the diaphragms
* Ribs take on a more horizontal appearance
Know what “Granular” looks like. Know what “Streaky” or “Ropy” looks like. My
good friends at Amazon are not capable of printing a clear picture o f these so I want you
to stop reading and
A. Go to google images
B. Search “Granular neonatal chest x-ray.’” Look at a bunch o f examples. Maybe even
download a few of them for review.
C. Search “Streaky Perihilar neonatal chest x-ray.” Look at a bunch o f examples.
Maybe even download a few o f them for review.
D. Search “Ropy neonatal chest x-ray.” Look at a bunch o f examples. Maybe even
download a few o f them for review.
Chest
random pearl
We are going to talk about the presence o f a pleural effusion as a
discriminator. One pearl is to look fo r an accentuated (thick) minor fissure on the right. If
you see that shit, kid probably has an effusion. Confirm by staring with fierce intensity at the
lung bases to look for obliteration o f the costophrenic sulcus.
High Volumes
+ Perihilar Streaky
Alphabet - MNoP
Meconium Aspiration
Non GB Neonatal
Pneumonia
Not High (low or
normal) Volumes
+ Granular
SSD
Group B Pneumonia
Meconium Aspiration
This typically occurs secondary to stress (hypoxia), and is more common in term or postmature
babies (the question stem could say “post term ” delivery). The pathophysiology is all
secondary to chemical aspiration.
Meconium Aspiration
trivia
- The buzzword “ropy appearance” o f asymmetric lung densities
- Hyperinflation with alternative areas o f atelectasis
- Pneumothorax in 20-40% o f cases
Meconium Aspiration
hyperinflation
How can it have hyperinflation?? Aren V the lungs fu l l o f sticky shit
(literally) ??? The poop in the lungs act like miniature bal 1-valves
(“floaters” 1 call them), causing air trapping - hence the increased lung
volumes.
Meconium Aspiration
reality vs multiple choice
“Meconium Staining ” on the amniotic fluid is common (like 15% o f all
births), but development o f “aspiration syndrome” is rare with only 5% o f those 15% actually have
aspiration symptoms. Having said that, if the question header bothers to include “Green colored
amniotic fluid” or “Meconium staining” in the question header they are giving you a major hint.
Don’t overthink a hint like this. I f they ask “What color was George Washington s white horse ? ” the
answer is NOT brown.
Transient Tachypnea of the Newborn (TTN)
The classic clinical scenario is a history o f c-section (vagina squeezes the fluid out of lungs
normally). Other classic scenario histories include “diabetic mother” and/or “maternal
sedation.” Findings are going to start at 6 hours, peak at one day, and be done by 3 days. You
are going to see coarse interstitial marking and fluid in the fissures.
Transient Tachypnea of the Newborn (TTN)
trivia
- Classic histories: C-Section, Maternal Sedation, Maternal Diabetes
- Onset: Peaks at day 1, Resolved by Day 3
- Lung Volumes - Normal to Increased
Surfactant-Deficient Disease (SDD)
This is also called hyaline membrane disease, or RDS. It’s a disease of pre-mature kids. The idea
is that they are bom without surfactant (the stuff that makes your lungs stretchy and keeps alveolar
surfaces open). It’s serious business and is the most common cause of death in premature
newborns. You get low lung volumes and bilateral granular opacities (just like B-hcmolytic
pneumonia). But, unlike B-hemolytic pneumonia you do NOT get pleural effusions. As a piece
of useful clinical knowledge, a normal plain film at 6 hours excludes SDD.
Surfactant Replacement Therapy
They can spray this crap in the kid’s lungs, and it makes a huge difference (decreased death rate
etc…). Lung volumes get better, and granular opacities will clear centrally after treatment. The
post treatment look of bleb-like lucencies can mimic PIE.
Surfactant Replacement Therapy
trivia
- Increased Risk of Pulmonary Hemorrhage
* Increased Risk of PDA
Neonatal Pneumonia (Beta-Hemolytic Strep - or “GBS”)
This is the most common type of pneumonia in newborns. It’s acquired during exit of the dirty
birth canal. Premature infants arc at greater risk relative to term infants. It has some different
looks when compared to other pneumonias (why I discuss it separately).
Neonatal Pneumonia (Beta-Hemolytic Strep - or “GBS”)
trivia
- It often has low lung volumes (other pneumonias have high)
- Granular Opacities is a buzzword (for this and SDD)
- Often (25%) has pleural effusion (SDD will not)
- LESS likely to have pleural effusion compared to the non Beta hemolytic version (25% vs 75%)
Neonatal Pneumonia (not Beta-Hemolytic Strep - “Non GB” or “Non GBS”)
Lots of causes. Typical look is patchy, asymmetric pcrihilar densities, effusions, and
hyperinflation. Will look similar to surfactant deficient disease but will be full term. Effusions are
also much more likely (they arc rare in SDD).
Persistent Pulmonary HTN
Also called “persistent fetal circulation”. Normally, the high pulmonary pressures seen in utero
(that cause blood to shunt around the lungs) decrease as soon as the baby takes his/her first breath.
Dr. Goljan (Step 1 wizard) calls this a “miracle,” and used this basic physiology to deny
evolution. When high pressures persist in the lungs it can be primary (the work of Satan), or
secondary from hypoxia (meconium aspiration, pneumonia, etc…). The CXR is going to show
the cause of the pulmonary HTN (pneumonia), rather than the HTN itself.
When I say “Post Term Baby, ”
You Say Meconium Aspiration
When I say “C-Section, ”
You say Transient Tachypnea
When I say “Maternal Sedation ”
You say Transient Tachypnea
When I say “Premature”
You say RDS
Solving Cases Using lung Volumes
High (flat diaphragms)
- Meconium Aspiration
- Transient Tachypnea
- Non BH Neonatal Pneumonia
Solving Cases Using lung Volumes
low
- Surfactant Deficiency (no pleural effusion)
* Beta-Hemolytic Pneumonia (gets pleural effusions)
Pulmonary Interstitial Emphysema (PIE)
When you have surfactant deficiency and they put you on a ventilator (which pulverizes your
lungs with PEEP), you can end up with air escaping the alveoli and ending up in the
interstitium and lymphatics. On CXR it looks like linear lucencies (buzzword). It’s a
warning sign for impending Pneumothorax. Most cases o f PIE occur in the first week of time
(bronchopulmonary dysplasia - which looks similar - occurs in patients older than 2-3
weeks). Surfactant therapy can also mimic PIE. The treatment is to switch ventilation
methods and/or place them PIE side down.
Pulmonary Interstitial Emphysema (PIE)
trivia
- Consequence of ventilation
- Usually occurs in the first week of life
- Buzzword = Linear Lucencies
- Warning Sign for Impending Pneumothorax
- Treatment is to put the affected side down
Pulmonary Interstitial Emphysema (PIE)
zebra
A total zebra is the progression of PIE to a large cystic mass. The thing can even cause
mediastinal mass effect.
Chronic Lung Disease - CLD / (Bronchopulmonary Dysplasia - BPD)
This is the kid bom premature (with resulting surfactant deficiency), who ends up being
tortured in ventilator purgatory. His/her tiny little lungs take a ferocious ass whipping from
positive pressure ventilation and oxygen toxicity — “barotrauma” they call it. This beating
essentially turns the lungs into scar, inhibiting their ability to grow correctly. That is why
people call this “a disease of lung growth impairment.”
Chronic Lung Disease - CLD / (Bronchopulmonary Dysplasia - BPD)
classic vignetter
Prolonged ventilation in a tiny (<1000 grams), premature kid (<32 weeks)
Chronic Lung Disease - CLD / (Bronchopulmonary Dysplasia - BPD)
classic look
Alternating regions of fibrosis (coarse reticular opacities), and hyper-aeration (cystic lucencies).
Chronic Lung Disease - CLD / (Bronchopulmonary Dysplasia - BPD)
buzzword
“Band like opacities”
Classic This vs That: CLD vs PIE
PIE = First week of life,
CLD = After 3 to 4
weeks’ postnatal age
Pulmonary Hypoplasia
This can be primary or secondary. Secondary causes seem to lend themselves more readily to multiple
choice questions. Secondary causes can be from decreased hemi-thoracic volume, decreased vascular
supply, or decreased fluid. The most common is the decreased thoracic volume, typically from a space
occupying mass such as a congenital diaphragmatic hernia (with bowel in the chest), but sometimes
from a neuroblastoma or sequestration. Decreased fluid, refers to the Potter Sequence (no kidneys ->
no pee -> no fluid -> hypoplastic lungs).
Bronchopulmonary Sequestration
These are grouped into intralobar and extralobar with the distinction being which has a pleural
covering. The venous drainage is different (intra to pulmonary veins, extra to systemic veins). You
can NOT tell the difference radiographically. The practical difference is age of presentation;
intralobar presents in adolescence or adulthood with recurrent pneumonias, extralobar presents in
infancy with respiratory compromise.
Bronchopulmonary Sequestration
intralobar overview
Much more common (75%). Presents
in adolescence or adulthood as recurrent pneumonias
(bacteria migrates in from pores of Kohn). Most
commonly in the left lower lobe posterior segment
(2/3s). Uncommon in the upper lobes. In
contradistinction from extralobar sequestration, it is
rarely associated with other developmental
abnormalities. Pathology books love to say “NO
pleural cover ” - but you can’t see that shit on CT or MR.
Bronchopulmonary Sequestration
intralobar quick
more common
presents in adolescence
recurrent infections
no pleural cover
pulmonary venous drainage
Bronchopulmonary Sequestration
extralobar overview
Less common of the two (25%).
Presents in infancy with respiratory compromise
(primarily because of the associated anomalies -
Congenital cystic adenomatoid malformation
(CCAM), congenital diaphragmatic hernia, vertebral
anomalies, congenital heart disease, pulmonary
hypoplasia). It rarely gets infected since it has its own
pleural covering. These are sometimes described as
part of a bronchopulmonary foregut malformation, and
may actually have (rarely) a patent channel to the
stomach, or distal esophagus. Pathology books love to
say “has a pleural cover ” - but you can’t see that shit
on CT or MR.
Bronchopulmonary Sequestration
extralobar quick
less common
presents in infancy
associated congenital anomalies
Bronchopulmonary Sequestration
gamesmanship
I say recurrent pneumonia in same area, you say intralobar sequestration.
Bronchogenic Cysts
Typically an incidental finding. They are generally solitary and unilocular. They typically do NOT communicate with the airway, so if they have gas in them you should worry about infection.
Congenital Cystic Adenomatoid Malformation (CCAM)
As the name suggests it’s a malformation of adenomatoid stuff that replaces normal lung. Most
of the time it only affects one lobe. There is no lobar preference (unlike CLE which favors the
left upper lobe). There are cystic and solid types (type 1 cystic, type 3 solid, type 2 in the
middle). There is a crop of knuckle heads who want to call these things CPAMs and have 5
types, which I ’m sure is evidence based and will really make an impact in the way these things
are treated. CCAMs communicate with the airway, and therefore at least components of them
can fill with air. Most of these things (like 90%) will spontaneously decrease in size in the third
trimester. The treatment (at least in the USA) is to cut these things out, because of the iddy bitty
theoretical risk of malignant transformation (pleuropulmonary blastoma, rhabdomyosarcoma).
What i f you see a systemic arterial feeder (one coming o ff the aorta) going to the CCAM ?
Then it’s not a CCAM, it’s a Sequestration. — mumble to yourself “nice try assholes”
Congenital Lobar Emphysema (CLE)
The idea behind this one is that you have bronchial pathology (maybe atresia depending on what
you read), that leads to a ball-valve anomaly and progressive air trapping. On CXR, it looks
like a lucent, hyper-expanded lobe.
Congenital Lobar Emphysema (CLE)
trivia
- It’s not actually emphysema - just air trapping secondary to bronchial anomaly
- It prefers the left upper lobe (40%)
- Treatment is lobectomy
Congenital Lobar Emphysema (CLE)
gamesmanship
•The classic way this is shown in case conference or case books is with a series of CXRs.
The first one has an opacity in the lung (the affected lung clears fluid slower than normal
lung). The next x-ray will show the opacity resolved. The following x-ray will show it
getting more and more lucent. Until it’s actually pushing the heart over.
Congenital Diaphragmatic Hernia (CDHs)
Most commonly they are Bochdalek type. B is in the Back - they are typically posterior and to
the left. The appearance on CXR is usually pretty obvious.
Congenital Diaphragmatic Hernia (CDHs)
trivia
- Usually in the Back , and on the left (Bochdalek)
- If it’s on the right - there is an association with GBS Pneumonia
- Mortality Rate is related to the degree o f pulmonary Hypoplasia
- Most have Congenital Heart Disease
- Essentially all are malrotated
Congenital Diaphragmatic Hernia (CDHs)
gamesmanship
•One trick is to show the NG tube curving into the chest.
Locational Strategy
Left Upper lobe
Think Congenital Lobar Emphysema (CLE) first But, remember CCAM has no lobar prevalence, so it can be anywhere
Locational Strategy
left lower lobe
Think Sequestration First
Congenital Diaphragmatic
Hernia (CDHs) favors this
side too
Special Situations in Peds Chests
viral
In all ages this is way more common than bacterial infection. Peribronchial edema is the
buzzword for the CXR finding. “Dirty” or “Busy” Hilum. You also end up with debris and mucus in
the airway which causes two things (1) hyperinflation and (2) subsegmental atelectasis. Respiratory
Syncytial Virus (RSV) - This will cause the typical non-specific viral pattern as well. However,
there is the classic testable predilection to cause a segmental or lobar atelectasis — particularly in the
right upper lobe.
Special Situations in Peds Chests
Round Pneumonia
Kids get round pneumonia. They love to show
this, and try to trick you into thinking it’s a mass. Younger than 8 you are
thinking round pneumonia, round pneumonia, round pneumonia - with S.
Pneumonia being the culprit. The PhD trivia is that these occur because you
don’t have good collateral ventilation pathways. Round pneumonia is
usually solitary, and likes the posterior lower lobes. Take home message: No
CT to exclude cancer, just get a follow up x-ray.
Special Situations in Peds Chests
Neonatal atypical peripheral atelectasis (NAPA)
It is best to think about this as a cousin or uncle of Round Pneumonia (they are in the
same family). It is essentially the same thing except it is peripheral. The
classic look is a round, pleural based “mass” in the apex of the lung.
Similarly to the “round pneumonia” this is a transient finding and will
resolve as the primary process improves.
Special Situations in Peds Chests
Lipoid Pneumonia
Classic history is a parent giving their newborn a teaspoonful of olive oil
daily to cultivate “a spirit o f bravado and manliness. ” Although this seems like a pretty solid plan, and
I can’t fault their intentions - it’s more likely to result in chronic fat aspiration. Hot Sauce is probably a
better option. Most people will tell you that bronchoalveolar lavage is considered the diagnostic
method of choice. CXR nonspecific - it is just airspace opacities. CT is much more likely to be the
modality used on the exam. The classic finding is low attenuation (-30 to -100 HU) within the
consolidated areas reflecting fat content
Special Situations in Peds Chests
Bronchial Foreign Body
The key concept is that it causes air trapping.
The lung may look more lucent (from air
trapping) on the affected side. You put the
affected side down and it will remain lucent
(from air trapping). Another random piece of
trivia is that under fluoro the mediastinum will
shift AWAY from the affected side on
expiration.
Special Situations in Peds Chests
Swyer James
This is the classic unilateral lucent lung. It typically occurs after a viral lung
infection in childhood resulting in post infectious obliterative bronchiolitis. The size of the affected
lobe is smaller than a normal lobe (it’s not hyper-expanded).
Special Situations in Peds Chests
Papillomatosis
Perinatal HPV can cause these soft tissue masses within the airway and lungs.
It’s also seen in adults who smoke. “Multiple lung nodules which demonstrate cavitation” is the
classic scenario. Some testable trivia includes the 2% risk of squamous cell cancer, and that
manipulation can lead to dissemination. The appearance of cysts and nodules can look like LCH
(discussed more in the thoracic chapter), although the trachea is also involved.
Special Situations in Peds Chests
Sickle Cell I Acute Chest
Kids with sickle cell can get “Acute chest.” Acute chest actually
occurs more in kids than adults (usually between age 2-4). This is the leading cause of death in sickle
cell patients. Some people think the pathology is as such: you infarct a rib -> that hurts a lot, so you
don’t breath deep -> atelectasis and infection. Others think you get pulmonary microvascular
occlusion and infarction. Regardless, if you see opacities in the CXR of a kid with sickle cell, you
should think of this.
Special Situations in Peds Chests
Cystic Fibrosis
So the sodium pump doesn’t work and
they end up with thick secretions and poor pulmonary clearance. The real damage is done by recurrent infections.
Special Situations in Peds Chests
Primary Ciliary Dyskinesia
The motile part of
the cilia doesn’t work. They can’t clear their lungs and get
recurrent infections. These guys have lots of bronchiectasis
just like CF. BUT, this time it’s lower lobe predominant
(CF was upper lobe
Bronchial foreign body
key point
A normal inspiratory CXR is meaningless. Don’t forget that the crayon / green bean is going
to be radiolucent. You need expiratory films to elicit air trapping. Normally, the bottom lung is gonna
turn white (move less air). If there is air trapping the bottom lung will stay black.
Sickle Cell I Acute Chest
gamesmanship
(how do you know it’s sickle cell?)
•Kid with Big Heart
•Kid with bone infarcts (look at the humeral heads)
•Kid with H shaped vertebra (look on lateral)
Cystic Fibrosis
things to know
•Bronchiectasis (begins cylindrical and progresses to
varicoid)
•It has an apical predominance (lower lobes are less
affected)
•Hyperinflation
•They get Pulmonary Arterial Hypertension
•Mucus plugging (finger in glove sign)
•Men are infertile (vas deferens is missing)
Cystic Fibrosis
trickery
• Fatty Replaced Pancreas on CT
• Abdominal Films with
Constipation
Biliary Cirrhosis (from blockage of intrahepatic bile ducts), and resulting portal HTN
Primary Ciliary Dyskinesia
Things to know
•Bronchiectasis (lower lobes)
•50% will have Kartageners (situs inversus). So, 50%
will not
•Men are infertile (sperm tails don’t work)
•Women are sub-fertile (cilia needed to push eggs
around)
This vs that
cystic fibrosis vs primary ciliary dyskinesia
CF: Upper Lobe Predominant - Brochiectasis Infertile - Men are Missing the Vas Deferens
Primary Ciliary dyskinesia: Lower Lobe Predominant - Bronchiectasis Infertile - Men’s Sperm Don’t Swim For Shit
Pleuropulmonary Blastoma (PPB)
This is a primary intrathroacic malignancy. They can look a lot like CCAMs and even have different types (cystic, mixed, solid). These
things are usually right sided, pleural based, and without chest wall invasion or calcifications.
No rib invasion (helps distinguish it from the Askin / Ewing Sarcoma o f the Chest Wall - if
they won’t tell you the age), No calcification. The more solid types can have mets to the brain
and bones. The cystic type seem to occur more in kids less than a year old, and be more benign.
Pleuropulmonary Blastoma (PPB)
things to know
- Big Fucking Mass (B.F.M.) in the chest o f a 1-2 year old
- Shouldn’t have an eaten-up rib (Askin tumors often do)
- 10% o f the time they have a multilocular cystic nephroma.
Umbilical Venous Catheter (UVC)
A UVC passes from the umbilical vein to the left
portal vein to the ductus venosus to a hepatic vein to
the 1VC. You don’t want the thing to lodge in the
portal vein because you can infarct the liver. The
ideal spot is at the 1VC - Right Atrium junction.
Development of a “Cystic Liver Mass” (Hematoma) can suggest
UVC erosion into the liver.
Umbilical Artery Catheter (UAC)
A UAC passes from the umbilicus, down to the
umbilical artery, into an iliac artery then to the aorta.
Positioning counts, as the major risk factor is renal
arterial thrombosis. You want to avoid the renal
arteries by going high (T8-T10), or low (L3-L5)
Things to know about UACs
- It goes down first
- It should be placed either high (T8-T10) or low (L3-L5)
- Omphalocele is a contraindication
UAC =
down then up
UVC =
straight up
ECMO - Extracorporeal Membrane Oxygenation
Neonatologists primarily use this device to torture sick babies - hopefully into revealing the
various government secrets they have stolen, or the location of their organization’s
underground lair. “Enhanced interrogation” or “temporizing measure o f last resort,” they call
it - to get around the Geneva Conventions.
Oh you want to pretend you can’t talk? Get the ECMO catheters!
Alternatively, it can be used as a last resort in neonatal sepsis, severe SSD, and meconium
aspiration. Actually, in cases of meconium aspiration ECMO actually does work (sometimes).
ECMO - Extracorporeal Membrane Oxygenation
types overview
There are two main types: (1) Veno-Arterial “V-A”,
and (2) Veno-Venous “V-V”
In both cases deoxygenated blood is removed from the
right atrium and pumped into a box (artificial lung) to
get infused with oxygen. The difference is in how it is
returned.
ECMO - Extracorporeal Membrane Oxygenation
V-A
In V-A, blood goes back to the Aorta (you can see why
this would help rest the left ventricle). The catheter is
usually placed at the origin o f the innominate or
“overlying the arch.”
ECMO - Extracorporeal Membrane Oxygenation
V-V
In V-V blood goes right back into the right atrium. In
this situation even if the lungs were totally clogged
with shit (meconium aspiration) and no oxygen
exchange was happening it wouldn’t matter because
the blood that is being pumped (RA -> RV ->
Pulmonary Artery) already has oxygen in it.
ECMO - Extracorporeal Membrane Oxygenation
V-A quick
Catheter Position: RA + Aorta (near the origin of the innominate artery)
Catheter Position: RA + Aorta (near the origin of the innominate artery)
ECMO - Extracorporeal Membrane Oxygenation
V-V quick
Catheter
Position:
RA+ RA
“Dual Lumen”
Lung Support
ECHO - Extracorporeal Membrane Oxygenation - Continued
Lung White Out = Normal
Mechanism is variable depending on who you asked. The way
1 understand it is that the airway pressure suddenly drops off causing atelectasis, plus you
have a change in the circulation pattern that now mimics the fetal physiology (mom =
artificial lung). Resulting oxygen tension changes lead to an edema like pattern. A multiple
choice trick could be to try and make you say it is worsening airspace disease, or reflects the
severity of the lung injury. Don’t fall for that. It’s an expected finding.
ECHO - Extracorporeal Membrane Oxygenation - Continued
Consequences of V-A
I mentioned on the prior page that they typically ligate the carotid
when they place the Arterial catheter. No surprise that they will be at increased risk for
neurologic ischemic complications as a result.
ECHO - Extracorporeal Membrane Oxygenation - Continued
Crucial Complication = Hemorrhage
The combination of anticoagulation (necessary in
ECMO) and being sick as stink puts these kids at super high risk for head bleeds. This is
why they will get screened for germinal matrix hemorrhage prior to being placed on ECMO
and then routinely screened with head ultrasounds (expertly read by the second year resident
on call).
Catheter Position Gamesmanship:
I think there are two likely ways a multiple choice question could be structured related to
ECMO catheter position. The first would be to show you a series of daily radiographs with the
latest one demonstrating migration of one or both catheters. Thats the easy way to do it.
The sneaky way would be to show you the
catheter with the lucent distal end and the dot
marker on the tip. This would be particularly
evil as there are tons of different catheter
brands and looks, but if I was going to try and
trick you, this would be the way that I would do
it.
In this case, the venous catheter looks falsely
high if judged by the lucent tip, but that round
metallic marker (near the black arrow) shows
the tip in the RA.
The arterial catheter “overlies the region of the
aortic arch,” which is normal.
mediastinal masses
anterior
Normal Thymus
Thymic Rebound
Lymphoma:
Germ Cell Tumor (GCT):
Normal Thymus
This is the most common mediastinal
“mass.” It’s terribly embarrassing to call a normal thymus a
mass, but it can actually be tricky sometimes. It can be
pretty big in kids less than 5 (especially in infants).
Triangular shape of the thymus is sometimes called the “sail
sign.” Not to be confused with the other 20 sail signs in
various parts of the body, or the spinnaker sail sign, which is
when pneumomediastinum lifts up the thymus.
Thymic Rebound
In times of acute stress (pneumonia, radiation, chemotherapy, bums), the
thymus will shrink. In the recovery phase it will rebound back to normal, and sometimes larger
than before. During this rebound it can be PET avid
Lymphoma:
This is the most common abnormal mediastinal mass in children (older
children and teenagers). Lymphoma vs Thymus can be tricky. Thymus is more in kids under 10,
Lymphoma is seen more in kids over 10. When you get around age 10, you need to look for
cervical lymph nodes to make you think lymphoma. If you see calcification, and the lesion has
NOT been treated you may be dealing with a teratoma. Calcification is uncommon in an untreated lymphoma.
Lymphoma:
complications
Compression o f SVC, Compression o f Pulmonary> Veins, Pericardial Effusion, Airway Compression.
Lymphoma:
all/leukemia
can appear very similar to Lymphoma (soft tissue mass in the anterior
mediastinum). In this scenario, most people will tell you that Lymphoma can NOT be
differentiated from Leukemia on imaging alone.
Germ Cell Tumor (GCT):
On imaging, this is a large anterior mediastinal mass arising from or at least next to the thymus. It comes in three main flavors,
Germ Cell Tumor (GCT):
teratoma
Mostly Cystic, with fat and calcium
Germ Cell Tumor (GCT):
seminoma
Bulky and Lobulated. “Straddles the midline ”
Germ Cell Tumor (GCT):
NSGCT
Big and Ugly - Hemorrhage
and Necrosis. Can get crazy and invade the lung.
Things that make you think the
thymus is a cancer!
• Abnormal Size for patients Age (really big in a 15 year old) • Heterogenous appearance • Calcification • Compression of airway or vascular structure
Middle mediastinal masses
lymphadenopathy
duplications cysts
lymphadenopathy
Middle mediastinal lymphadenopathy is most often from granulomatous disease (TB or Fungal), or from lymphoma.
Mediastinal Adenopathy Trivia
mononucleosis
Cause: EBV (-90%), CMV (-10%)
Classic Scenario: Adolescent with hilar adenopathy, splenomegaly,
and fatigue.
Trivia: Rash after Antibiotics (Amoxicillin)
Trivia: “No sports for 3 weeks” - to avoid splenic injury
Mediastinal Adenopathy Trivia
primary TB
Distribution of nodes in usually unilateral, right hilar, right paratracheal
Lower and Middle lobe consolidation is common
Mediastinal Adenopathy Trivia
histoplasmosis
Midwest and Southeast United States
Most have normal CXRs
Can have hilar adenopathy
Mediastinal Adenopathy Trivia
coccidioidomycosis
Southwest United States
Usually looks like consolidation and nodules
Can have hilar adenopathy
Mediastinal Adenopathy Trivia
lymphoma
Often cited as the “most common” anterior mediastinal mass in a kid. Hilar involvement (usually bilateral) is more common with Hodgkin
Mediastinal Adenopathy Trivia
sarcoid
Uncommon in children — it usually presents in the early-mid 20s.
Case reports of early onset Sarcoid exist.
Duplications cysts
These fall into three categories (a) bronchogenic, (b) enteric,
(c) neuroenteric. The neuroenterics are traditionally posterior mediastinal.
Duplications cysts
bronchogenic
water attenuation - close to the trachea or bronchus. Trivia:
• Tend to be middle mediastinal (70%), the rest are in the hilum
• Typically filled with mucus or fluid
Duplications cysts
enteric/esophageal
water attenuation close to the esophagus (lower in the
mediastinum). Trivia:
• Abutment o f the esophagus is the key finding.
• Can communicate with the lumen of the esophagus - and have air/fluid levels.
• Usually on the right, involving the distal esophagus
• Can be middle or posterior mediastinal in location
• Second most common G1 lumen duplication cyst (distal ileum #1)
Posterior mediastinal masses
Neuroblastoma
Ewing Sarcoma
Askin Tumor (Primitive Neuroectodermal tumor of the chest wall):
Neuroenteric Cyst
Extramedullary Hematopoiesis
Neuroblastoma
This is the most common posterior mediastinal mass in a child under 2. This
is discussed in complete detail in the GU PEDs section. I’ll just mention that compared to abdominal
neuroblastoma, thoracic neuroblastoma has a better outcome. It may involve the ribs and vertebral
bodies. Also, remember that Wilms usually mets (more than neuroblastoma) to the lungs, so if it’s in
the lungs don’t forget about Wilms.
Neuroblastic mediasetinal tumors
most aggressive and immature to least aggressive and mature
neuroblastoma > ganglioneruoblastoma > ganglioneuroma
When Compared with Neuroblastoma, Ganglioneuromas are
• Less Aggressive
• More Circumscribed (less invasive)
• Less Likely to have Calcifications (although they still can)
• Pound in Older Children
These tumors can NOT be differentiated with imaging alone
(but that doesn’t mean someone can’t write a multiple choice
question asking you to try).
Askin Tumor (Primitive Neuroectodermal tumor of the chest wall):
This is now considered part of the Ewing Sarcoma spectrum, and is sometimes called an Ewing
sarcoma of the chest wall. They tend to displace adjacent structures rather than invade early on (when
they get big they can invade). They look heterogenous, and the solid parts will enhance.
Neuroenteric Cyst
By convention these are associated with vertebral anomalies (think
scoliosis, hemivertebrae, butterfly vertebrae, split cord, etc..) - think cyst protruding out of an unsealed
canal / defect. The cyst does NOT communicate with CSF, is well demarcated, and is water density.
Favor the lower cervical and thoracic regions.
Extramedullary Hematopoiesis
This occurs in patients with myeloproliferative
disorders or bone marrow infdtration (including sickle cell). Usually, this manifests as a big liver and
big spleen. However, in a minority of cases you can get soft tissue density around the spine
(paraspinal masses), which are bilateral, smooth, and sharply delineated.
Extramedullary Hematopoiesis
This occurs in patients with myeloproliferative
disorders or bone marrow infdtration (including sickle cell). Usually, this manifests as a big liver and
big spleen. However, in a minority of cases you can get soft tissue density around the spine
(paraspinal masses), which are bilateral, smooth, and sharply delineated.
Strategy - The Anterior Mediastinal Mass
Lymphoma
In a kid just assume it’s Hodgkins (which means it’s gonna involve the
thymus). Why assume Hodgkins ? Hodgkins is 4x more common than NHL. Hodgkins
involves the thymus 90% of the time.
Strategy - The Anterior Mediastinal Mass
How the hell do you tell a big ass normal thymus in a little baby vs a lymphoma?
My main move is to go age. Under 10 = Thymus, Over 10 = Lymphoma.
Strategy - The Anterior Mediastinal Mass
Thymic Rebound
If the test writer is headed in this direction they MUST either (a)
bias you with a history saying stuff like “got off chemo” or “got off corticosteroids” or
(b) show you a series of axial CTs with the thing growing and maintaining normal
morphology. I think “a” is much more likely.
Strategy - The Anterior Mediastinal Mass
The Funk
In general just think morphology / density:
• Soft Tissue - Kinda Homogenous = Think Lymphoma or Hyperplasia
• Fat = Germ Cell Tumor (Why God!? Why Klinefelters!?)
• Water = Congenital Stuff - Think Lymphangiomas
Strategy - The Posterior
Mediastinal Mass
Under 10
Think malignant,
Think neuroblastoma.
Strategy - The Posterior
Mediastinal Mass
Think benign.
If it’s a round mass- Think about
Ganglioneuromas & Neurofibromas
If it’s cystic (and there is scoliosis) think
Neuroenteric Cyst
If they show you coarse bone
trabeculation - with an adjacent mass (or
a history of anemia) - Think
Extramedullary Hematopoiesis
Strategy - The B.F.M.
“Big Fucking Mass” If you see a B.F.M. in the chest o f a kid, you basically have two choices: (1) Askin Tumor (PNET / Ewings) - * AGE 10+, look for an eaten up rib. (2) Pleuropulmonary Blastoma *AGE is typically less than 2.
Esophageal Atresia /TE fistula:
This can occur in multiple subtypes, with the classic ways of showing it being a frontal CXR with an NG tube stopped in the upper neck, or a fluoro study (shown lateral) with a blind ending sac or communication with the tracheal tree. There are 5 main subtypes, only 3 (shown above) are worth knowing (being familiar with) for the purpose of the exam.
Esophageal Atresia /TE fistula:
Things to know
•Diagnosis is made with a Fluoro swallow exam
•Most Important Thing To Know are the VACTERL associations (more on this later)
• The most common subtype is the N-Type (blind ended esophagus, with distal esophagus hooked up
to trachea
• Excessive Air in the Stomach = H type (can also be with N type)
• No Air in the Stomach = Esophageal Atresia
• The presence of a right arch (4%) must be described prior to surgery (changes the approach).
Esophageal Atresia /TE fistula:
gamesmanship
Fake out for TE fistula is simple aspiration. Look for the presence or absence of laryngeal penetration to tell them apart (if shown a dynamic Fluoro swallow exam).
VACTERL:
This is extremely high yield. VACTERL is a way of remembering that certain
associations are seen more commonly when together (when you see one, look for the others).
VACTERL:
frequency
V - Vertebral Anomalies (37%) A - Anal (imperforate anus) (63%) C - Cardiac (77%) TE - Tracheoesophageal Fistula or Esophageal Atresia (40%) R - Renal (72%) L - Limb (radial ray) - 58%
VACTERL:
diagnosis
VACTERL association is diagnosed when 3
or more of the defined anomalies affect a
patient.
Therefore, keep investigating when 1 -2 of
these anomalies are found.
The heart and kidneys are the most
commonly affected organs in this
VACTERL:
trivia
If both limbs are involved, then both kidneys tend to be involved. If one limb is involved, then
one kidney tends to be involved
Esophageal Atresia
stricture
Around 30% of kids with a repaired esophageal atresia will end up with a focal
anastomotic stricture. Strictures can also be seen with caustic ingestion (dishwashi
Esophageal Foreign Bodies
Kids love to stick things in their mouths (noses and ears).
This can cause a lot of problems including direct compression o f the airway, perforation, or even
fistula to the trachea. Stuff stuck in the esophagus needs to be removed.
Esophageal Foreign Bodies
The esophagus is a dirty sock, it flexes to accommodate that big piece of steak you didn’t even bother to chew. The trachea is rigid, like that math teacher I had in high school (who hated music… and colors), but unlike the math teacher it has a flexible membrane in the back.
The point of me mentioning this is to help you problem solve a “where is the coin ”
type question. The esophagus will accommodate the coin so it can be turned in any direction. The trachea is rigid and will force the coin to rotate
into the posterior membrane — so it will
be skinny in the AP direction.
Ingested Metallic Foreign Bodies
Magnets
One magnet is ok. Two or more magnets is a
problem. The reason is that they can attract
each other across intestinal walls leading to
obstruction, necrosis, perforation, and a law suit.
Surgical Consult
NOT an MRI (dumbass)
Ingested Metallic Foreign Bodies
AA or AAA Batteries
Less of a problem relative to other types of
batteries, but can cause serious problems if you
need them for the DVR control because Game of
Thrones season 7 is on (spoiler it sucked).
Serial plain film exams.
Remove if they stay in
the stomach for more
than 2 days
Ingested Metallic Foreign Bodies
Disc Batteries
They look like coins, except they have two rings. The literature is not clear, but it appears that modern batteries rarely leak (leaking is bad - caustic chemicals, heavy metals etc..).
Stuck in the esophagus
= big problem, gotta
get them out within 2 hours.
Stuck in the stomach =
problem, gotta get
them out within 4 days.
Ingested Metallic Foreign Bodies
Coins
(Including Pennies
minted prior to 1982)
Copper Pennies are relatively safe.
Make sure it is not a disc battery
(coins have one order ring, disc
battery has two).
Remove if: Retention in the esophagus for more than 24 hours or Stomach for more than 28 days.
Ingested Metallic Foreign Bodies
Pennies
-minted after 1982
Those minted after 1982 contain mostly Zinc
which when combined with stomach acid can
cause gastric ulcerations, and if absorbed in
great enough quantity can cause zinc toxicosis
(which is mainly pancreatic dysfunction /
pancreatitis). The ulcers are the more likely thing
to happen, so just remember that.
So how the hell can you tell the date of a penny
that is swallowed? Either (a) the question stem
will have to say something like - “2 year old child
playing with father’s collection of 1984 pennies” ,
or the more likely (b) showing you the penny with
characteristic radiolucent holes - from erosion.
remove rom stomach
Ingested Metallic Foreign Bodies
lead
Usually Lead Paint Dust - or Any object with lead paint.
Bad because the gastric acid leads to immediate absorption.
Remove immediately
from stomach. Distal
passable must be
confirmed.
Ingested Metallic Foreign Bodies
shar object nos
Esophagus = Remove Immediately
Stomach = Remove Immediately
Post Pylorus = Follow vs Surgery — if it does perforate the small bowel it
will be at the IC valve
Pulmonary Sling
• The only variant that goes between the esophagus and the trachea.
• Classic question is that this is associated with tracheal stenosis (which is actually primary
and not secondary to compression).
• High association with other cardiopulmonary and systemic anomalies: hypoplastic right lung,
horseshoe lung, TE-fistula, imperforate anus, and complete tracheal rings.
• Treatment is controversial but typically involves surgical repositioning o f the artery
Double Aortic Arch
most common symptomatic ascular ring anomaly
impressions on the anterior aorta and posterior trachea
Left Arch with Aberrant Right Subclavian Artery
• Most Common Aortic Arch Anomaly — not
necessarily symptomatic.
• “Dysphagia Lusoria” - fancy Latin speak (therefore
high yield) for trouble swallowing in the setting of
this variant anatomy
• “Diverticulum of Kommerell” pouch like
aneurysmal dilatation of the proximal portion o f an
aberrant right subclavian artery
Bowel Obstruction ( in the neonate 1
High
Midgut Volvulus /
Malrotation
Duodenal Atresia
Duodenal Web
annular pancrease
jejunal atresia
Bowel Obstruction ( in the neonate 1
Low
hirschprung disease
meconium plug syndrome
ileal atresia
meconium ileus
anal atresia/colonic atresia
Single Bubble
Gastric (antral or pyloric) atresia.
Double Bubble
Duodenal Atresia
Duodenal Atresia Trivia
• 30% have Downs • 40% have polyhydramnios and are premature • The“singlc atresia” - cannulation error • On multiple choice test the “double bubble” can be shown on 3rd trimester OB ultrasound, plain film, or on MRI.
Triple Bubble
Jejunal Atresia. When you call jejunal atresia,
you often prompt search for additional atresias (colonic). Just remember
!^ ,’ P that jejunal atresia is secondary to a vascular insult during development.
multiple atresia
vascular error
Single Bubble with Distal Gas
Can mean nothing (lotta air swallowing). If the clinical
history is bilious vomiting , this is ominous and can
be midgut volvulus (surgical emergency). Next test
would be emergent Upper GI.
Double Bubble with Distal Gas
Seeing distal gas excludes duodenal atresia. The DDx is a
duodenal web, duodenal stenosis, or midgut
volvulus. Next step would be upper GI.
Multiple Diffusely Dilated Loops
Suggestive o f a low obstruction (ileum or colon).
Next step is contrast enema. If the contrast enema is
normal you need to follow with upper GI (to
exclude an atypical look for midgut volvulus).
Mildly Dilated, Scattered Loops
“Sick Belly” - Can be seen with proximal or distal obstruction. Will need Upper GI and contrast enema.
Malrotation
Normally, the developmental rotation o f the gut places the ligament of
Trietz to the left o f the spine (at the level o f the duodenal bulb). If mother nature fucks up and
this doesn’t happen, you end up with the duodenum to the right o f the midline (spine). These
patients are at increased risk for midgut volvulus and internal hernias. If you see the
appearance o f malrotation and the clinical history is bilious vomiting, then you must suspect
midgut volvulus
Malrotation
trivia
•Associated with Heterotaxy Syndromes. Associated with Omphaloceles.
•Classically shown as the SMA to the right of the SMV (on US or CT).
•False Positive on UGI - Distal Bowel Obstruction displacing the duodenum (because of
ligamentous laxity).
I say “Non-Bilious Vomiting”
You Say Hypertrophic Pyloric Stenosis
next step ultrasound
I say “Bilious Vomiting”
You Say Mid Gut Volvulus (till proven otherwise)
Next Step ? Upper GI
Corkscrew Duodenum
This is diagnostic of
midgut volvulus (surgical emergency). The appearance
is an Aunt Minnie.
Ladd’s Bands
In older children (or even adults)
obstruction in the setting of malrotation will present as
intermittent episodes o f spontaneous duodenal
obstruction. The cause is not midgut volvulus (a
surgical emergency) but rather kinking from Ladd’s Bands.
Ladd’s Bands
what is it
We are talking
about a fibrous stalk of peritoneal tissues that fixes the
cecum to the abdominal wall, and can obstruct the duodenum.
Complete Duodenal Obstruction
Strongly associated with midgut volvulus. If you were thinking duodenal atresia, look for distal air (any will do) to exclude that thought.
Ladd’s Procedure
Procedure to prevent midgut volvulus. Traditionally, the Ladd’s Bands are divided, and the appendix is taken out. The small bowel ends up on the right, and the large bowel ends up on the left. They are fixed in place by adhesions (just by opening the abdomen). It is still possible to develop volvulus post Ladd’s (but it’s rare - 2-5%).
Ladd’s Procedure
steps
- Divide the Adhesive Ladds Bands
- Widen the Mesentery to a safe distance
- Take out the appendix (bill extra for that)
Partial Duodenal Obstruction
If the kid is vomiting this might be from extrinsic
narrowing (Ladd band, annular pancreas), or
intrinsic (duodenal web, duodenal stenosis).
You can’t tell.
Hypertrophic Pyloric Stenosis
Thickening of the gastric pyloric musculature, which results in progressive obstruction. Step 1 buzzword is “non-bilious vomiting.” Here is the most likely multiple choice trick; this does NOT occur at birth or after 3 months.
There is a specific age range o f 2-12 weeks (peak at 3-6 weeks).
Criteria is 4mm and 14mm (4mm single wall, 14mm length).
The primary differential is pylorospasm (which will relax during exam). The most common pitfall during the exam is gastric over distention, which can lead to displacement o f the antrum and pylorus - leading to false negative.
False positive can result from off axis measurement.
The phenomenon of “paradoxical aciduria” has been described, and is a common buzzword.
Gastric Volvulus
Organoaxial
The greater curvature flips over the lesser curvature (rotation along the long axis). This is seen in old ladies with paraesophageal hernias.
Gastric Volvulus
•Mesenteroaxial
Twisting over the mesentery (rotation along short axis). The antrum flips near the GE junction. Can cause ischemia and needs to be fixed. Additionally this type causes obstruction. This type is more common in kids.
Duodenal Web:
This is best thought
of as “almost duodenal atresia. ” The
reason I say that is, just like duodenal
atresia, this occurs from a failure to
canalize, but instead o f a total failure of
canalization (like duodenal atresia) this
bowel is only partially canalized, leaving
behind a potentially obstructive web.
Duodenal Web
things to know
- Because the web is distal to ampulla of Vater - you get bile-stained emesis - Associated with malrotation and Downs syndrome - The “wind sock” defonnity is seen more in older kids - where the web-like diaphragm has gotten stretched.
Annular Pancreas
Essentially an embryologic screw up (failure o f ventral bud to rotate
with the duodenum), that results in encasement o f the duodenum.
In Kids = Think Duodenal Obstruction
In Adults = Think Pancreatitis
Annular Pancreas
on ct
Look for pancreatic tissue
(same enhancement as the nearby
normal pancreas) encircling the
descending duodenum.
Annular Pancreas
on fluoro
Look for an extrinsic narrowing of the duodenum. Obviously this is non-specific (typical barium - voodoo), use the location and clinical history to bias yourself.
“Low Obstruction” in a Neonate
You basically have 4 choices: Normal,
Short Microcolon, Long Microcolon, and a Caliber Change from micro to normal.
Short Microcolon -
• Think about Colonic Atresia
Long Microcolon
“Meconium Ileus
ONLY in patients with CF.
The pathology is the result of thick sticky meconium
causing obstruction o f the distal ileum. Contrast will
reach ileal loops, and demonstrate multiple filling
defects (meconium). This can be addressed with an
enema.
Long Microcolon
Distal Ileal Atresia
This is the result o f
intrauterine vascular insult. Contrast will NOT reach
ileal loops. This needs surgery.
Caliber Change
•Small Left Colon (Meconium Plug)
Syndrome
This is a transient functional colonic
obstruction, that is self limited and relieved by
contrast enema.
*Most Testable Fact:
It is NOT associated with CF.
*2nd Most Testable Fact:
It is seen in infants of diabetic mothers 01
if mom received magnesium sulfate for eclampsia
Caliber Change
•Hirschsprung Disease
Failure of the
ganglion cells to migrate and innervate the distal
colon. Affected portions o f the colon are small
in caliber, whereas the normally innervated
colon appears dilated.
•Hirschsprung Disease
Trivia
- It’s 4:1 more common in boys.
- 10% association with Downs.
- Diagnosis is made by rectal biopsy.
•Hirschsprung Disease
How it can be Shown
-Enema - Rectum smaller than the Sigmoid
“Recto-sigmoid ratio < 1”
-Enema - Rectum with “sawtooth pattern”
Represents bowel spasm
•Hirschsprung Disease
Presentation:
(1) Newborn who fails to have BM > 48 hours (or classically > 72 hours) (2) “Forceful passage o f meconium after rectal exam” (3) One month old who shows up “sick as stink” with NEC bowel
Total Colonic Aganglionosis
This is a super rare variant o f Hirschsprungs, and
can mimic microcolon. The piece of commonly asked trivia is that it can also involve the
terminal ileum.
Meconium Peritonitis
This is a potential complication o f bowel atresia
or meconium ileus. It has a very characteristic
look. It’s a calcified mass in the mid
abdomen , traditionally shown on plain film. It
is the result of a sterile peritoneal reaction to an
in-utero bowel perforation.
Usually, the perforation seals off prior to birth
and there is no leak.
Imperforate or Ectopic Anus
Imperforate or Ectopic Anus
Is a y “Baby with no asshole”
you say “VACTERL ”
you say “Screening US fo r tethered cord”
-Obstruction in an Older Child
ddx
Classic D D x “A IM ” -
Appendicitis, Adhesions
Inguinal Hernia, Intussusception
Midgut Volvulus, Meckels
Appendic itis
In children older than 4 this is the most common cause for bowel obstruction. I f they
show this in the PEDs section it’s most likely to be on ultrasound. In that case you can expect a blindending
tube, non-compressible, and bigger than 6 mm.
Inguinal He rn ia:
Big points are that indirect hernias
are more common in kids, they are lateral to the inferior epigastric, and incarceration is the most common
complication. Umbilical hernias are common in kids, but rarely incarcerate.
Trivia to know: This is the most common cause o f obstruction in boy 1 month - 1 year
Intussusc eption
The age range is 3 months - 3 years, before or after that you should think o f lead
points (90% between 3 months and 3 years d o n ’t have lead points). The normal mechanism is forward
peristalsis resulting in invagination o f proximal bowel (the intussusceptum) into lumen o f the distal bowel
(the intussuscipiens). They have to be bigger than 2.5 cm to ma tte r (in most cases- these are enterocolic),
those that are less than 2.0 cm are usually small bowel-small bowel and may reduce spontaneously within
minutes. Just like an appendix, in the peds section, I would anticipate this shown on ultrasound as either
the target sign or pseudo-kidney.
Intussusc eption
reducing trivia
exam)
• Recurrence: Usually within 72 hours
• Success Rates - 80-90% with air (Henoch-Schonlein purpura has a
reduced success rate)
• Risk o f Perforation - 0.5%
• Air causes less peritonitis (spillage o f fecal material) than barium
• Pressure should NOT exceed 120 mniHg
• Needle decompression would be the next step if they perforate and get tension pneumoperitoneum.
Intussusc eption
ways to ask
(1) what is it ?-
these should be straight forward as targets or pseudo kidneys, (2) lead
points - stu ff like HSP (vasculitis), Meckle diverticulum, enteric
duplication cysts, and (3) reduction trivia.
Me cke ls Diverticulum
This is a congenital diverticulum o f the distal ileum. A piece o f total trivia is
that it is a persistent piece o f the omphalomesenteric duct. Step 1 style, “rule o f 2s” occurs in 2% o f the
population, has 2 types o f heterotopic mucosa (gastric and pancreatic), located 2 feet from the IC valve, it’s
usually 2 inches long (and 2 cm in diameter), and usually has symptoms before the child is 2. I f it has
gastric mucosa (the ones that bleed typically do) it will take up Tc-Pertechnetate ju s t like the stomach
(hence the Meckel’s scan).
Me cke ls Diverticulum
trivia
- Can get diverticulitis in the Meckels (mimic appendicitis)
- GI Bleed from Gastric Mucosa (causes 30% o f symptomatic cases)
- Can be a lead point for intussusception (seen with inverted diverticulum)
- Can Cause Obstruction
Gastroschisis
Extra-abominal evisceration of neonatal bowel (sometimes stomach and liver)
through a paraumbilical wall defect.
Gastroschisis
things to know
- It does NOT have a surrounding membrane (omphalocele docs)
- It’s always on the RIGHT side.
- Associated anomalies are rare (unlike omphalocele).
- Maternal Serum AFP will be elevated (higher than that of omphalocele)
- Outcome is usually good
- For some reason they get bad reflux after repair.
- Associated with intestinal atresias.
Omphalocele
Congenital midlinc defect, with herniation of gut at the base of the umbilical cord.
Omphalocele
trivia
•It DOES have a surrounding membrane (gastroschisis does
not)
•Associated anomalies are common (unlike gastroschisis)
•Trisomy 18 is the most common associated chromosomal
anomaly
•Other associations: Cardiac (50%), Other GI, CNS, GU,
Turners, Klinefelters, Beckwith-Wiedemann, Pentalogy of
Cantrell
•Outcomes are not that good, because of associated
syndromes.
•Umbilical Cord Cysts (Allantoic Cysts) are associated
Pentalogy of Cantrell
- Omphalocoele
- Ectopia Cordis
(abnormal location o f heart) - Diaphragmatic Defect
- Pericardial Defect
or Sternal Cleft - Cardiovascular malformations
This vs T hat— Gastroschisis vs Omphalocele
Gastroschisis
Herniated bowel loop through the
ventral body wall
NOT surrounded by a membrane
Umbilicus is Normal - positioned to the left o f the
defect (defect is on the right)
defect is on the right
asociated anomalies are rare
associated with intestinal atresias
cause: probably environment which explains an association with bowel atresia
This vs T hat— Gastroschisis vs Omphalocele
omphalocele
Herniated bowel loop through the
ventral body wall
Surrounded by a membrane (peritoneum)
Umbilicus contains herniated b ow e l, and therefore is
NOT normal
defect is midline
High A ssociation with Cardiac (50%) defects and
Chromosomal Abnormalities
Multiple Syndromic Associations including Turners,
Klinefelters, Beckwith-Wiedemann, and the
Legendary Pentalogy o f Cantrell
Cause: Probably Genetic - which explains the
associations with the various syndromes
Duodenal Hematoma
Classic injury from bicycle handlebars (or child abuse!. You can also
see this as a complication from endoscopy. You could be shown retroperitoneal gas as a way to
suggest perforation.
Enteric Duplication Cysts
These are developmental anomalies (failure to canalize). They
don’t have to communicate with the GI lumen but can. They are most commonly in the ileal region
(40%). They have been known to cause in utero bowel obstruction / perforation.
Enteric Duplication Cysts
strategy
Strategy: A common way to show this is a cyst in the abdomen (on ultrasound). If you have a random
cyst in the abdomen you need to ask yourself - “does this have gut signature? ”
• Cyst with Gut Signature = Enteric Duplication Cyst
• Cyst without Gut Signature = Omental Cyst
• WTF is “Gut Signature ?” - It’s alternating bands of hyper and hypo echoic signal - supposedly
representing different layers of bowel.
Enteric Duplication Cysts
trivia
30% of the time they are associated with vertebral anomalies.
Distal Intestinal Obstruction Syndrome
This is a cause of bowel obstruction in an older
kid (20 year old) with cystic fibrosis. This is sometimes called the “meconium ileus equivalent, ”
because you end up with a distal obstruction (as the name implies) secondary to dried up thick stool. It
more commonly involves the ileum / right colon. Kids who get this, are the ones who aren’t compliant
with their pancreatic enzymes.
Mesenteric Adenitis
Self-limiting, usually viral inflammatory condition of mesenteric lymph
nodes. It is a classic clinical mimic of appendicitis. The finding is a cluster of large right lower quadrant lymph nodes.
Necrotising Enterocolitis (NEC)
This is bad news. The general thinking is that you have an immature bowel mucosa (from being
premature or having a heart problem), and you get translocated bugs through this immature bowel. It’s
best thought of as a combination of ischemic and infective pathology.
Necrotising Enterocolitis (NEC)
who gets it
- Premature Kids (90% within the first 10 days of life)
- Low Birth Weight Kids ( < 1500 grams)
- Cardiac Patients (sometimes occult) - they can be full term
- Kids who had perinatal asphyxia
- Hirschsprung Kids that go home and come back - they present around month 1.
Necrotising Enterocolitis (NEC)
what does it look like
• Pneumatosis - most definitive finding; Look for Portal Venous Gas Next
• Focal Dilated Bowel (especially in the right lower quadrant) - the terminal ileum / right colon is the
region most affected by NEC
• Featureless small bowel , with separation (suggesting edema).
• Unchanging bowel gas pattern — this would be a dirty trick - showin
Necrotising Enterocolitis (NEC)
Pneumatosis vs Poop - The age old question
- First question - has the kid been feed? No food = No poop.
* Second question - is it staying still? Poop will move, Pneumatosis will stay still.
Necrotising Enterocolitis (NEC)
trivia
Use of maternal breast milk is the only parameter associated with decreased incidence of NEC.
Pancreas
CF
The pancreas is nearly always (90%) with CF patients.
Inspissated secretions cause proximal duct obstruction leading to the
two main changes in CF: (1) Fibrosis (decreased T1 and T2 signal) and
the more common one (2) fatty replacement (increased Tl).
Patients with CF diagnosed as adults tend to have more pancreas
problems than those diagnosed as children. Those with residual
pancreatic exocrine function can have bouts of recurrent acute
pancreatitis. Small (l-3mm) pancreatic cysts are common.
Pancreas
CF
trivia
- Complete fatty replacement is the most common imaging finding in adult CF
- Enlarged with fatty replacement = lipomatous pseudohypertrophy of the pancreas.
- Fibrosing Colonopathy: Thick walled right colon as a complication of enzyme replacement therapy
Shwachman-Diamond Syndrome
The 2nd most common cause of pancreatic insufficiency in kids (CF #1). Basically, it’s a kid with diarrhea, short stature, and
eczema. Will also cause lipomatous pseudohypertrophy of the pancreas.
Dorsal Pancreatic Agenesis
You only have a ventral bud (the dorsal bud forgets
to form). Since the dorsal buds makes the tail, the appearance is that of a pancreas without a
tail. All you need to know is that (1) this sets you up for diabetes (most o f your beta cells are
in the tail), and (2) it’s associated with polysplenia.
Pancreatitis
The most common cause of pancreatitis in peds is trauma (seat belt).
Pancreatitis NAT
Another critical point to make is that non-accidental trauma can present as pancreatitis.
If the kid isn’t old enough to ride a bike (handle bar injury) or didn’t have a car wreck (seat belt injury) you need to think NAT.
.Tumors of the Pediatric Pancreas
Even at a large pediatric hospital its uncommon to see more
than 1-2 of these a year. Obviously, they are still fair game for multiple choice
Solid and Papillary Epithelial Neoplasm (SPEN)
The most common pediatric solid
tumor. It’s found in female adolescents (usually asian, or black). The outcomes are pretty good after
surgical resection. If you get shown a case in the peds setting this is probably it.
Peds Pancreatic Mass
Age 1 = Pancreatoblastoma
Age 6 = Adenocarcinoma
Age 15 = SPEN
Liver masses
age 0-3
Infantile Hepatic Hemangioma
Hepatoblastoma
Mesenchymal Hamartoma
Infantile Hepatic Hemangioma
Often 1. Associated with high output CHF, this is
classically shown as a large heart on CXR plus a mass in
the liver. The aorta above the hepatic branches o f the
celiac is often enlarged relative to the aorta below the
celiac because o f differential flow. Skin hemangiomas
are present in 50%. Endothelial growth factor is
elevated. These can be associated with Kasabach-Merritt
Syndrome (the platelet eater).
Infantile Hepatic Hemangioma
how do they do
Actually well. They tend to spontaneously involute without therapy over
months-years - as they progressively calcify.
Hepatoblastoma:
Most common primary liver tumor o f childhood (< 5).
The big thing to know is that it’s associated with a bunch
o f syndromes - mainly hemi-hypertrophy, Wilms,
Beckwith-Weidemann crowd. Prematurity is a risk factor.
This is usually a well circumscribed solitary right sided
mass, that may extend into the portal veins, hepatic veins,
and IVC. Calcifications are present 50% o f the time. AFP
is elevated. Another piece of trivia is the hepatoblastoma
may cause a precocious puberty from making bHCG.
Hepatoblastoma:
I would know 3 things
(1) Associated with Wilms, (2) AFP, (3) Precocious Puberty
Mesenchymal Hamartoma
This is the predominately cystic mass (or multiple cysts), sometimes
called a “developmental anomaly.” Because it’s a “developmental
anomaly” it shouldn’t surprise you that the AFP is negative.
Calcifications are UNCOMMON. What is common is a large portal
vein branch feeding the tumor.
liver masses
Age > 5
HCC
Fibrolamellar Subtype
Undifferentiated Embryonal Sarcoma
HCC
This is actually the second most common liver cancer in kids. You’ll see them in kids with cirrhosis (biliary atresia, Fanconi syndrome, glycogen storage disease). AFP will be elevated.
Fibrolamellar Subtype
This is typically seen in younger patients (<35) without
cirrhosis and a normal AFP. The buzzword is central scar. The scar is similar to the one seen
in FNH with a few differences. This scar does NOT enhance, and is T2 dark (the FNH scar is
T2 bright). As a point of trivia, this tumor is Gallium avid. This tumor calcifies more often
than conventional HCC.
Undifferentiated Embryonal Sarcoma
This is the pissed off cousin of the
mesenchymal hamartoma. It’s also cystic, but the mass is much more aggressive. It will be a
hypodense mass with septations and fibrous pseudocapsule. This mass has been known to
rupture.
liver masses any age
Mets: Think about Wilms tumor or Neuroblastoma
Now. there are several other entities that can occur in the liver o f young children / teenagers
including; Hepatic Adenoma, Hemangiomas, Focal Nodular Hyperplasia, and Angio
Sarcoma. The bulk o f these are discussed in greater detail in the adult GI chapter.
Choledochal cysts
are congenital dilations of the bile ducts -classified into 5 types by
some dude named Todani. The high yield trivia is type 1 is focal dilation o f the CBD and is by
far the most common. Type 2 and 3 are super rare. Type 2 is basically a diverticulum o f the
bile duct. Type 3 is a “choledochocele.” Type 4 is both intra and extra hepatic. Type 5 is
Caroli’s, and is intrahepatic only. I’ll hit this again in the GI chapter.
Caroli’s
is an AR disease associated with polycystic kidney disease and medullary sponge
kidney. The hallmark is intrahepatic duct dilation, that is large and secular. Buzzword is
“central dot sign” which corresponds to the portal vein surrounded by dilated bile ducts.
AR Polycystic Kidney Disease
This will be discussed in greater detail in the renal
section, but kids with AR polycystic kidney disease will have cysts in the kidneys, and
variable degrees of fibrosis in the liver. The degree o f fibrosis is actually the opposite of
cystic formation in the kidneys (bad kidneys ok liver, ok kidneys bad liver).
Hereditary Hemorrhagic Telangiectasia (Osler-Weber-Rendu):
Autosomal dominant disorder characterized by multiple AVMs in the liver and lungs. It leads
to cirrhosis, and a massively dilated hepatic artery. The lung AVMs set you up for brain
abscess.
Biliary Atresia
If you have prolonged newborn jaundice (> 2 weeks) you should think
about two things (1) neonatal hepatitis, and (2) Biliary Atresia. It’s critical to get this
diagnosis right because they need corrective surgery (Kasai Procedure) prior to 3 months.
Patients with biliary atresia really only have atresia of the ducts outside the liver (absence of
extrahepatic ducts), in fact they have proliferation o f the intrahepatic ducts. They will
develop cirrhosis without treatment and not do well
Trivia to Know about Biliary Atresia
• Associations with Polysplenia, and Trisomy 18
• Gallbladder may be absent (normal gallbladder - supports neonatal hepatitis)
• Triangle Cord Sign - triangular echogenic structure by the portal vein - possibly remnant of
the CBD.
• Hepatobiliary Scintigraphy with 99m Tc-IDA is the test o f choice to distinguish (discussed
in the Nukes Chapter).
• Alagille Syndrome: This is a total zebra. All you need to know is hereditary cholestasis,
from paucity o f intrahepatic bile ducts, and peripheral pulmonary stenosis. The purpose o f a
liver biopsy in biliary atresia is to exclude this diagnosis.
Gallstones
If you see a peds patient with gallstones think sickle cell.
Sickle Cell
spleen
These kids bodies have spleen better days - as the spleen will typically
enlarge progressively and then eventually auto-infarct and shrink (during the first decade). If
the spleen remains enlarged it can run into problems - mainly acute splenic sequestration
crisis.
Sickle Cell
splenic sequestration
This is the second most common cause o f death in SC patients
younger than 10. We are talking about the situation in which the spleen becomes a greedy
little pig and tries to hog all the blood for itself.
Sickle Cell spleen
gamesmanship splenic sequestration
History o f abdominal pain or vital signs suggesting low volume (high HR,
low BP) with a big spleen. Remember most kids with sickle cell will have smaller spleens
(auto infarct) so a big spleen should be your clue.
Sickle Cell
other problems if your spleen stays too big
Other problems you can run into if your spleen stays big are abscess formation and large
infarcts. These large infarcts are not the same pathophysiology as the “auto-infarct” you
typically think of with sickle cell. These are the big wedge shaped infarcts (hypo-perfusion on
CT). As a point of trivia, infarcted splenic tissue should look hypoechoic on US, with linear
“bright bands ” — google that if you haven’t seen it before.
Sickle Cell
autoinfarcted spleen
This is different than the massive infarct in that it is typically the
combined effort of numerous tiny, unnoticeable, and repetitive micro occlusions leading to
progressive atrophy. Supposedly this doesn’t hurt (large infarcts do). This tends to occur
early and is usually “complete” by age 8. The typically look is going to be a tiny (possibly
calcified) spleen. When I say tiny - we are talking like 1cm. In the imaginary world of
multiple choice you might not even see the fucking thing
cant see the spleen
Auto Infarct = Sickle Cell
Sickle Cell
too small spleen gamesmanship
If you don’t see the spleen but you do see a gallbladder full o f stones in a kid
less than 15 - you should think Sickle Cell.
Polysplenia and Asplenia
Heterotaxia syndromes are clutch for multiple choice
tests. The major game played on written tests is “left side vs right side. ”
Heterotaxia syndromes
So what the hell does that mean
Let me break this down like a cardboard box that you intend
to put in your recycling … because this gets pretty fucking complicated. I like to start in the
lungs. The right side has two fissures (major and minor). The left side has just one fissure.
So if 1 show you a CXR with two fissures on each side, (a left sided minor fissure), then the
patient has two right sides. Thus the term “bilateral right sidedness.”
Heterotaxia syndromes
What else is a right sided
structure?
The liver. So,
these patients won’t have a
spleen (the spleen is a left
sided structure).
Heterotaxia syndromes
The opposite is true.
Since the spleen is on the left, a
“bilateral left sided” patient
will have polysplenia.
Heterotaxia syndromes
Aorta/IVC
This relationship is a little more confusing when you try to reason it out. The
way I keep it straight is by remembering that the IVC is usually on the right. If you are
“bilateral left” then you don’t have a regular IVC — hence the azygos continuation. Then
just remember that the other one (flipped IVC/Aorta) is the other one.
Right Isomerism
Reversed (Aorta/ ICV)
-Asplenia
Left Isomerism
Azygos Continuation
-Polysplenia
H e te ro ta x ia Syndromes
right sided
two fissures in left lung
asplenia
increased cardiac malformations
reversed aorta/ivc
H e te ro ta x ia Syndromes
left sided
one fissure in right lung
polysplenia
less cardiac malformations
azygos continuation of the ivc
Situs Vocab
• Situs Solitus - Instead o f just saying normal, you can be an asshole and say “Situs Solitus. ”
• Situs Inversus Totalis - Total mirror image transposition o f the abdominal and thoracic
stuff.
• Situs Ambiguus (Ambiguous) - This is a tricky way of saying Heterotaxy, o f which you can
have left or right “isomerism.”
“Isomerism”
1 guess some asshole really liked organic chemistry…. This is a fancy
way of saying bilateral right or bilateral left
Situs Solitus
Normal
• Gastric Bubble on Left • Larger part of Liver on Right • Minor fissure on Right
Situs
Inversus
• Gastric Bubble on Right • Larger part of Liver on Left • Minor fissure on Left • Inverted Bronchial Pattern • Associated with Primary Ciliary Dyskinesia
V.H. with T
Left
Isomerism
• Absent Minor Fissures • Interrupted I VC • Polysplenia • Biliary Atresia ( 10%)
Top 4 Things for Peds Gl
biliary atresia
• Congenital liver fibrosis -» cholangiopathy
-» neonatal jaundice (after 1 week of life)
• US: Bright band of tissue (triangular cord
sign) near branching of common bile duct;
small or absent gallbladder (fasting ~ 3
hours)
• Scintigraphic: No tracer excretion into bowel
by 24 hours
• Biopsy to exclude = Zebra Alagille syndrome
• Treated with Kasai procedure
Top 4 Things for Peds Gl
malrotation
• Duodenum to the right of the midline • Increased risk for mid gut volvulus, and internal hernia • “Bilious vomiting” • SMA to the right of the SMV
Top 4 Things for Peds Gl
heterotaxia syndromes
Right Sided:
two fissures in left lung
asplenia
increased cardiac malformations
reversed aorta/ivc
LEft sided:
one fissure in right lung
polysplenia
less cardiac malformations
azygos continuation of the ivc
Top 4 Things for Peds Gl
vacterl
V - Vertebral Anomalies (37%) A - Anal (imperforate anus) (63%) C - Cardiac (77%) TE - Tracheoesophageal Fistula or Esophageal Atresia ( 40%) R - Renal (72%) L - Limb (radial ray) - 58%
Renal Agenesis
Most likely way to test this
Show unilateral agenesis on prenatal US - as an absent renal artery (in
view of the aorta) or oligohydramnios - with followup questions on associations. Or make it super
obvious with a CT / MRI and ask association questions.
Renal Agenesis
Unilateral Absence Association
• 70% of women with unilateral renal agenesis have associated genital anomalies (usually
unicornuate uterus, or a rudimentary horn).
• 20% of men are missing the epididymis, and vas deferens on the same side they are missing the
kidney. PLUS they have a seminal vesicle cyst on that side.
Renal Agenesis
Potter Sequence
Insult (maybe ACE inhibitors) = kidneys don’t form, if kidneys don’t form you can’t
make piss, if you can’t make piss you can’t develop lungs (pulmonary hypoplasia).
Renal Agenesis
Lying Down Adrenal or “Pancake Adrenal” Sign
describes the elongated appearance of the adrenal
not normally molded by the adjacent kidney. It can be used to differentiate surgical absent vs
congenitally absent.
Horseshoe Kidney
This is the most common fusion anomaly. The kidney gets hung up on the
IMA. Questions are most likely to revolve around the complications / risks:
• Complications from Position - Easy to get smashed against vertebral body - kid shouldn’t play
football or wrestle.
• Complications from Drainage Problems: Stones, Infection, and Increased risk of Cancer (from
chronic inflammation) - big ones are Wilms, TCC, and the Zebra Renal Carcinoid.
• Association Syndrome Trivia - Turner’s Syndrome is the classic testable association.
Crossed Fused Renal Ectopia
One kidney comes across the midline and fuses with the
other. Each kidney has its own orthotopic ureteral
orifice to drain through. It’s critically important to the
patient to know that “the Ectopic Kidney is
Inferior. ” The left kidney more commonly crosses
over to the right fusing to the normal right kidney
lower pole. Complications include stones, infection,
and hyponephrosis (50%).
The classic way to show this is two axial CTs. The
first at the level of the kidneys hinting that one
kidney may be absent. The second through the
bladder (on a delayed phase) showing two opacified ureters.
Congenital UPJ Obstruction
This is the most common congenital anomaly of the GU tract in neonates. About 20% of the time,
these are bilateral. Most (80%) of these are thought to be caused by intrinsic defects in the circular
muscle bundle of the renal pelvis. Treatment is a pycloplasty. A Radiologist can actually add value
Congenital UPJ Obstruction
1970 called and they want to know how to tel! the difference between a prominent extrarenalpelvis
v.v a congenital UPJ obstruction
Whitaker Test ”, which is a urodynamics study combined with an antegrade pyelogram.
Congenital UPJ Obstruction
Classic history
Teenager with flank pain after drinking “lots of fluids.”
Congenital UPJ Obstruction
classic trivia
These do NOT have dilated ureters (NO HYDROURETER).
Autosomal Recessive Polycystic Kidney
Disease (ARPKD)
These guys get HTN and renal
failure. The liver involvement is different than the adult
form (ADPKD). Instead of cysts they have abnormal
bile ducts and fibrosis. This congenital hepatic fibrosis is
ALWAYS present in ARPKD. The ratio of liver and
kidney disease is inverse. The worse the liver is the
better the kidneys do. The better the liver is the worse
the kidneys arc. Death is often from portal hypertension.
Autosomal Recessive Polycystic Kidney
Disease (ARPKD)
ultrasound
On ultrasound the kidneys are smoothly enlarged and diffusely echogcnic, with a loss of corticomedullary
differentiation. In utero you sometimes will not see
urine in the bladder. Cysts tend to be tubular and spare
the cortex
ARPKD us quick
Big Bright, with Lost
Corticomedullary Differentiation.
Neonatal Renal Vein Thrombosis
This is an associated condition of maternal diabetes,
sepsis, and dehydration. It is typically unilateral (usually left). The theory is that it starts peripherally
and progresses toward the hilum. When acute, will cause renal enlargement. When chronic, will
result in renal atrophy.
Neonatal Renal Artery Thrombosis
This occurs secondary to umbilical artery
catheters. Unlike renal vein thrombosis it does NOT present with renal enlargement but instead severe hypertension.
Prune Belly (Eagle Barrett Syndrome)
This is a malformation triad which occurs in males. Classically
shown on a babygram with a kid shaped like a pear (big wide belly).
Prune Belly (Eagle Barrett Syndrome)
triad
• Deficiency of abdominal musculature
• Hydroureteronephrosis
• Cryptorchidism
(bladder distention interferes with descent o f testes)
Congenital (primary) MEGAureter
This is a “wastebasket” term for an enlarged
ureter which is intrinsic to the ureter (NOT the result of a distal obstruction). Causes include
(1) distal adynamic segment (analogous to achalasia, or colonic Hirschsprungs), (2) reflux at
the UVJ, (3) it just wants to be big (totally idiopathic). The distal adynamic type “obstructing
primary megaureter,” can have some hydro, but generally speaking an absence o f dilation o f
the collecting system helps distinguish this from an actual obstruction.
Retrocaval Ureter (circumcaval)
This is actually a
problem with the development o f the IVC, which grows in a
manner that pins the ureter. Most o f the time it’s asymptomatic,
but can cause partial obstruction and recurrent UTI. I VP will
show a “reverse J” or “fishhook” appearance o f the ureter.
Duplicated System
The main thing to know
about duplicated systems is the so-called “Weigert-
Meyer Rule” where the upper pole inserts inferior and
medially. The upper pole is prone to ureterocele
formation and obstruction. The lower pole is prone to
reflux. Kidneys with duplicated systems tend to be
larger than normal kidneys. In girls, a duplicated
system can lead to incontinence (ureter may insert
below the sphincter - sometimes into the vagina).
Duplicated system
upper v lower
- Upper Pole Obstructs
- Lower Pole Refluxes
Upper Pole (obstructed / dilated) inserts Inferior and Medial
Lower Pole
inserts Superior
and Lateral
Ureterocele
A cystic dilation o f the intravesicular
ureter, secondary to obstruction at the ureteral orifice. IVP
(or US) will show the “cobra head” sign, with contrast
surrounded by a lucent rim, protruding from the contrast
filled bladder. This is associated with a duplicated system
(specifically the upper pole).
Ectopic Ureter
The ureter inserts distal to the external sphincter in the vestibule. More
common in females and associated with incontinence (not associated with incontinence in
men). Ureteroceles are best demonstrated during the early filling phase o f the VCUG.
Posterior Urethral Valves
This is a fold in the posterior urethra that leads to
outflow obstruction and eventual renal failure (if it’s
not fixed). It is the most common cause of urethral
obstruction in male infants.
Posterior Urethral Valves
trivia
The fold is a Wolfian Duct tissue remnant
Posterior Urethral Valves
classic VCUG
The key finding on VCUG is an
abrupt caliber change between the dilated posterior
urethra and normal caliber anterior urethra.
Posterior Urethral Valves
Fetal MRI
The MR1 would have to show hydro in
the kidney and a “key-hole” bladder appearance.
Posterior Urethral Valves
Prenatal ultrasound
- Hydronephrosis
- Bladder Dilation
- Oligiohydramnios
Posterior Urethral Valves
buzzword
“Peri-renal fluid collection” is a buzzword, and it’s
the result o f fomiceal rupture. Obviously that is
non-specific and can be seen with any obstructive pathology.
Non-Obstructive Causes of
Hydro in Baby Boys
- Vesicoureteral Reflux (VUR)
- Primary Megaureter
- Prune Belly = Zebra
Obstructive Causes of
Hydro in Baby Boys
- PUV
- UPJ Obstruction
- Ureteral Ectopia
Hydro workup
Hydronephrosis on Routine Prenatal Screening > repeat ultrasound once born > goes away in most > if persistent > VCUG to ealuate anatomy (gold standard), adjunctive MAG 3 to evaluate function and drainage (obstructive vs non obstructive), MR urography offers functionand structure but requires sedation in little kids
Vesicoureteral Reflux (VUR)
Normally, the ureter enters the bladder at an
oblique angle so that a “valve” is developed.
If the angle of insertion is abnormal
(horizontal) reflux can develop. This can
occur in the asymptomatic child, but is seen
in 50% o f children with UTIs. The
recommendations for when the boy/girl with
a UTI should get a VCUG to evaluate for
VUR is in flux (not likely to be tested). Most
of the time VUR resolves by age 5-6.
Vesicoureteral Reflux (VUR)
trivia
Hydronephrosis is the most common
cause of a palpable renal “mass” in childhood.
Vesicoureteral Reflux (VUR)
grading system
There is a grading system fo r VUR which goes 1-5.
One is reflux halfway up the ureter,
Two is reflux into a non-dilated collecting system, (calyces still pointy),
Three you have dilation o f the collecting system, and calyces get blunted
Four the system gets mildly tortuous,
Five the system is very tortuous
Vesicoureteral Reflux (VUR)
a sneaky trick
A sneaky trick would be to show the echogenic mound near the UVJ, that results from
injection o f “deflux”, which is a treatment urologist try. Essentially, they make a bubble with
this proprietary compound in the soft tissues near the UVJ and it creates a valve (sorta).
Anyway, they show it in a lot o f case books and textbooks so just like a midget using a urinal -
remember to stay on your toes.
Vesicoureteral Reflux (VUR)
pearl
Chronic reflux can lead to scarring. This scarring can result in
hypertension and/or chronic renal failure
Vesicoureteral Reflux (VUR)
additional pearl
If the reflux appears to be associated with a “hutch” diverticulum - people
will use the vocabulary “Secondary” VUR rather than Primary VUR. The treatment in this
case will be surgical. Ureteroceles, Posterior Valves, Neurogenic Bladder - are all causes of
Secondary VUR.
Vesicoureteral Reflux (VUR)
normal
-Intravesicular
ureter is oblique
Vesicoureteral Reflux (VUR)
reflux
intraversicular ureter is horizontal
“Hutch” Diverticula
- Occur at or adjacent (usually just above) the UVJ.
- Caused by congenital muscular defect
- Difficult to see on US — better seen with VCUG.
- They are “dynamic” and best seen on the voiding (micturition)
- If associated with VUR will often be surgically resected
The Urachus
The umbilical attachment to the bladder (started out being called the allantois, then
called the Urachus). This usually atrophies into the umbilical ligament. Persistent canalization can
occur along a spectrum (patent, sinus, diverticulum, cyst).
The Urachus
triiva 1
Most common complication of
urachal remnant = infection
The Urachus
trivia 2
Urachal anomalies are twice as common in boys
relative to girls
The Urachus
trivia 3
The most important piece of trivia is that when
these guys get cancer, it’s adenocarcinoma (90% of
cases). To hint at this multiple choice test writers will
often use the phrase “midline bladder structure
urachal spectrum
Normal Obliterated Urachus (only the ligament remains)
Patent Urachus
Vesicourachal Diverticulum
Urachal Cyst
Umbilical Urachal Sinus
Bladder Exstrophy
This is a herniation of the urinary
bladder through a hole in the anterior infra-umbilical abdominal wall.
Bladder Exstrophy
what to know
• Increased incidence of Malignancy in the extruded bladder
• It’s Adenocarcinoma - just like a Urachal Remnant would
get
• Aunt Minnie “Manta Ray Sign” - with unfused pubic
bones. This looks like a monster wide pubic symphysis on
an AP pelvic radiograph.
Cloacal Malformation
gu and gi both drain into a common openeing (like a birk) this only happens in females
Neurogenic Bladder
1 will discuss this more in the adult Urinary chapter, but for kids I want you
to think about spinal dysraphism (tethered cord, sacral agenesis, and all the other fucked up spine stuff).
Renal mass quick
neonate
nephroblastomasosis
mesoblastic nephroma
Renal mass quick
around age 4
wilms
wilms variants
lymphoma
multilocular cystic nephroma
Renal mass quick
teenager
rcc
lymphoma
Rapid Review Trivia
mesoblastic nephroma
Solid Tumor o f Infancy ” (you can be born with it)
Rapid Review Trivia
nephroblastomatosis
“Nephrogenic Rests” - left over embryologic crap that didn’t go away
Might turn into wilms (bilateral wilms especially)
“Next Step” - f/u ultrasound till 7-8 years old
Variable appearance
Rapid Review Trivia
wilms
90% + Renal Tumors
“Solid Tumor o f Childhood” - Never born with it
Grows like a solid ball (will invade rather than incase)
Met to the lung (most common)
Rapid Review Trivia
clear cells wilms
met to bone
Rapid Review Trivia
rhabdoid wilms
Brain Tumors
It fucks you up, it takes the money (it believes in nothing Lebowski)
Rapid Review Trivia
multi cystic nephroma
Micheal Jackson Tumor (Young Boys, Middle Age Women)
Big cysts that don’t communicate
Septal Enhancement
Can’t Tell it is not Cystic Wilms (next step = resection)
Rapid Review Trivia
rcc
“Solid Tumor o f Adolescent”
Syndromes - VHL, TS
rapid review trivia
renal lymphoma
Non-Hodgkin
Multifocal
Solid Age renal masses 0-3
Nephroblastomatosis
Mesoblastic Nephroma
Nephroblastomatosis
These are persistent nephrogenic rests beyond 36
weeks. It’s sorta normal (found in 1% of
infants). But, it can be a precursor to Wilms
so you follow it. When Wilms is bilateral,
99% of the time it had nephroblastomatosis
first. It goes away on its own (normally).
It should NOT have necrosis - this makes
you think Wilms. It has a variable
appearance, and is often described as
“homogeneous.” Although more commonly
a focal homogeneous ball, the way it’s
always shown in case conferences and case
books is as a hypodense rind.
Ultrasound screening q 3 months till age 7-8 is the usual routine - to make sure it doesn’t go
Wilms on you.
-Hypodense Rind -
Mesoblastic Nephroma
“Solid renal tumor o f infancy.” This is a fetal hamartoma,
and generally benign. It is the most common neonatal renal tumor (80% diagnosed in the first
month on life). Often involves the renal sinus. Antenatal ultrasound may have shown
polyhydramnios.
Pearl: If it really looks like a Wilms, but they are just too young (< 1 year) then call it mesoblastic nephroma.
Cystic Age renal mass 0-3
Multicystic Dysplastic Kidney
Multicystic Dysplastic Kidney
You have multiple tiny cysts forming in utereo.
What you need to know is (1) that there is “no functioning renal tissue,” (2) contralateral renal
tract abnormalities occur like 50% o f the time (most commonly UPJ obstruction).
Multicystic Dysplastic Kidney
mcdk vs bad hydro
- In hydronephrosis, the cystic spaces are seen to communicate.
- In difficult cases renal scintigraphy can be useful. MCDK will show no excretory function.
Multicystic Dysplastic Kidney
pearl
MCDK has MACROscopic cysts that do NOT communicate
Solid renal mass Around Age 4
Wilms
Wilms
associated sydromes overgrowth
• Beckwith-Wiedemann - Macroglossia (most common
finding), Omphalocele, Hemihypertrophy, Cardiac, Big Organs.
• Sotos - Macrocephaly, Retarded (CNS stuff), Ugly Face
Wilms
associated sydromes nonovergrowth
• WAGR - Wilms, Aniridia, Genital, Growth Retardation
• Drash - Wilms, Pseudohermaphroditism, Progressive
Glomerulonephritis
Wilms
bilateral
About 5-10% will have bilateral disease ( “Synchronous Bilateral Wilms ”)
Wilms variants
(look ju s t like Wilms)
• Clear Cell - likes to go to bones (lytic)
• Rhabdoid - “Terrible Prognosis” - Associated with aggressive Rhabdoid brain tumors
Wilms nevers
• NEVER Biopsy suspected Wilms
(you can seed the tract and up the stage)
• Wilms NEVER occurs before 2 months of age
(Neuroblastoma can)
Wilms in a 1 year old ?
Think about associated syndromes. Wilms loves to pal around with:
• Hemihypertrophy,
• Hypospadias,
• Cryptorchidism
I Say Beckwith-
Wiedemann
You Say,
•Wilms,
•Omphalocele,
•Hepatoblastoma
Cystic renal mass Around Age 4
Multilocular Cystic Nephroma
Multilocular Cystic Nephroma
“Non-communicating, fluid-tilled locules,
surrounded by thick fibrous capsule.” By
definition these things are characterized by
the absence of a solid component or necrosis.
There is a classic bimodal occurrence
(4 year old boys, and 40 year old women).
I like to think o f this as the Michael Jackson
lesion - it loves young boys and middle-aged
women
Multilocular Cystic Nephroma
buzzword
“protrude into the renal pelvis.”
Multilocular Cystic Nephroma
turbonerds
One of my favorite jokes has been this “Michael Jackson lesion” to help remember
the age distribution. Unfortunately - a bunch of Academic Nerds got together and
decided that the pediatric cystic nephromas arc their own thing now, and the adult
ones are their own thing - with the words “adult cystic nephromas” and “pediatric
cystic nephroma” as the preferred nomenclature. Assholes…. ruined a great joke.
Multilocular Cystic Nephroma
gamesmanship
Board exams usually lag a few years behind these kinds of changes. So if you get
a question asking about the age distribution, you may want to still go with the bimodal occurrence -
especially if they don’t say “adult” or “peds” — just make sure there isn’t another more correct
answer. This is where reading all the choices is critically important. Mind reading is also helpful.
Don’t forget to read the mind of the person who wrote the question - so you can understand his or
her bias.
Solids renal mass in T e e n a ger
Renal Lymphoma and RCC can occur in teenagers. Renal lymphoma can occur in 5 year olds as well.
Solids renal mass in T e e n a ger
Renal Lymphoma and RCC can occur in teenagers. Renal lymphoma can occur in 5 year olds as well.
Rhabdomyosarcoma
This is the most common bladder cancer in humans less than 10
years of age. They are often infiltrative, and it’s hard to tell where they originate from.
“Paratesticular Mass” is often a buzzword. They can met to the lungs, bones, and nodes.
The Botryoid variant produces a polypoid mass, which looks like a bunch of grapes. I’ll discuss
this again in the testicle section.
Neuroblastoma
Isn’t a Renal Mass, but is frequently contrasted with Wilms so I want to
discuss it in the renal section. It is the most common extra-cranial solid childhood malignancy.
They typically occur in very young kids (you can be born with this). 95% of cases occur
before age 10. They occur in the abdomen more than the thorax (adrenal 35%,
retroperitoneum 30%, posterior mediastinum 20%, neck 5%).
Neuroblastoma
staging
Things that up the stage include
crossing the midline, and contralateral positive
nodes. These things make it Stage 3.
Neuroblastoma
better prognosis
Diagnosis in Age < 1, Thoracic Primary, Stage 4S.
Neuroblastoma
associations
- NF-1, Hirschsprungs, DiGeorge, Beckwith Wiedemann
* Most are sporadic
Neuroblastoma
random trivia
• Opsomyoclonus (dancing eyes, dancing feet) - paraneoplastic syndrome associated with
neuroblastoma.
• “Raccoon Eyes” is a common way for orbital neuroblastoma mets to present
• MIBG is superior to Conventional Bone Scan for Neuroblastoma Bone Mets
• Neuroblastoma bone mets are on the “lucent metaphyseal band DDx”
• Sclerotic Bone mets are UNCOMMON
• Urine Catecholamines are always (95%) elevated
Neuroblastoma
stage 4s high yield
• Less than 1 year old
• Distal Mets are Confined to Skin, Liver, and
Bone Marrow
• Excellent Prognosis.
**A common distractor is to say 4S goes to
cortical bone. This is false! It’s the marrow.
Neuroblastoma
quick
Age: usually less than 2 (can occur in utero)
calcifies 90%
encases vessels (doesnt invade)
poorly marginated
mets to bones
Wilms
quick
Age: Usually around age 4 (never before 2 months)
Calcifies Rarely (<10%)
Invades Vessels (doesn’t encase)
Well Circumscribed
Doesn’t usually met to bones (unless clear cell
Wilms variant). Prefers lung.
Neonatal Adrenal Hemorrhage
This can occur in the setting o f birth
trauma or stress.
Neonatal Adrenal Hemorrhage
trivia
Neonatal adrenal hemorrhage is associated with scrotal hemorrhage
THIS v.s THAT: Hemorrhage VS Neuroblastoma:
• Ultrasound can usually tell the difference (adrenal hemorrhage is anechoic and
avascular, neuroblastoma is echogenic and hyper-vascular).
• MRI could also be done to problem solve if necessary (Adrenal Hemorrhage low T2 ,
Neuroblastoma high T2).
Gamesmanship - “Next Step” Adrenal mass of a neonate
Neonates that are sick enough to be in the hospital hemorrhage their fucking adrenals all the
time. An adrenal hemorrhage can look just like a mass on ultrasound. Yes, technically it
should be anechoic and avascular - but maybe your tech sucks, or maybe you don’t get shown
a picture they just tell you it’s a mass. The question writer is most likely going to try and
trick you into worrying about a neuroblastoma (which is also going to be a mass in the
adrenal).
Gamesmanship - “Next Step” Adrenal mass of a neonate
next step
Sticking a needle in it, sedating the kid for MRI, or exposing him/her to the
radiation o f CT, PET, or MIBG are all going to go against the “image gently” propaganda
being pushed at academic institutions. Plus it’s unnecessary. As is true with most things in
radiology, they either get better or they don’t. Hemorrhage is going to resolve. The cancer is
not. So the first step is going to be followup ultrasound imaging
Gamesmanship - History of “adrenal insufficiency” ?
Does that help you in the setting o f a newborn adrenal mass?
Nope. Most cases are actually caused by a 21 alpha hydroxylase deficiency (congenital
adrenal hyperplasia). Those tend to look different than hemorrhage or a mass- they are more
“cerebriform.” The problem is you can acquire adrenal insufficiency from neoplastic
destruction (neuroblastoma) or regular good old fashioned hemorrhage.
Hydrometrocolpos
Essentially the vagina won’t drain the uterus. This
condition is characterized on imaging by an expanded
fluid-filled vaginal cavity with associated distention of
the uterus.
Hydrometrocolpos
presentation
You can see it presenting in infancy as a mass, or as a
teenager with delayed menarche.
Hydrometrocolpos
causes
Causes include imperforate hymen (most common),
vaginal stenosis, lower vaginal atresia, and cervical
stenosis
Hydrometrocolpos
testing
For multiple choice trivia think about this as a “midline
pelvic mass” , which can cause hydronephrosis (mass
effect from distended uterus).
Hydrometrocolpos
trivia
Trivia: Associated with Uterus Didelphys (which often
~75% has a transverse vaginal septum)
ovarian torsio
In an adult, ovarian torsion is almost always due to a mass. In a child, torsion can
occur with a normal ovary, secondary to excessive mobility o f the ovary. As described in the
GYN chapter you are going to see an enlarged (swollen) ovary, with peripheral follicles, with or
without arterial flow. What is “enlarged” ? Unlike an adult you can’t really use a fixed number
to call the ovary enlarged (ovarian volumes in the peds setting are notoriously variable). The
solution is to compare the ovary in question to the contralateral size. Suspect torsion if the ovary
is at least 3 times the size of the opposite “normal” ovary. Fluid-Debris Levels within the
displaced follicles is another described adolescent ovarian torsion finding.
ovarian masses
About two-thirds of ovarian neoplasms are benign dermoids/teratomas (discussed in
detail in the GYN chapter). The other one third are cancer. The cancers are usually germ cells
(75%). Again, mural nodules and thick septations should clue you in that these might be cancer.
Peritoneal implants, ascites, and lymphadenopathy, are all bad signs and would over-ride
characteristics of the mass.
Hydrocele
Collection of serous fluid and is the most common cause of painless scrotal
swelling. Congenital hydroceles result from a patent processus vaginalis that permits entry of
peritoneal fluid into the scrotal sac.
Complicated Hydrocele (one with septations):
This is either a hematocele vs pyocele. The distinction is clinical.
Varicocele
Most of these are idiopathic and found in adolescents and young adults. They are
more frequent on the left. They are uncommon on the right, and if isolated (not bilateral) should
stir suspicion for abdominal pathology (nutcracker syndrome, RCC, retroperitoneal fibrosis).
Varicocele next step
Isolated right-sided varicocele = Abdomen CT
Exclude the extrinsic mass, renal vein thrombus, or
portal hypertension causing a splenorenal shunt
Scrotal HSP
This vasculitis is the most common cause of idiopathic scrotal edema
Acute Pain in or around the Scrotum
The top three considerations in a child with acute scrotal pain are (1) torsion of the testicular
appendage, (2) testicular torsion, and (3) epididymo-orchitis.
Epididymitis
The epididymal head is the most common part involved. Increased size and
hyperemia are your ultrasound findings. This occurs in two peaks: under 2 and over 6. You can
have infection of the epididymis alone or infection of the epididymis and testicle (isolated orchitis
is rare).
Orchitis
Nearly always occurs as a progressed epididymitis. When isolated the answer is mumps.
Torsion of the Testicular Appendages
This is the most common cause of acute
scrotal pain in age 7-14. The testicular appendage is some vestigial remnant of a mesonephric
duct. Typical history is a sudden onset of pain, with a Blue Dot Sign on physical exam (looks like
a blue dot). Enlargement of the testicular appendage to greater than 5 mm is considered by some
as the best indicator of torsion
Torsion of the Testicle
Results from the testis and spermatic cord twisting within the
serosal space leading to ischemia. The testable trivia is that it is caused by a failure o f the tunica
vaginalis and testis to connect or a “Bell Clapper Deformity”. This deformity is usually bilateral,
so if you twist one they will often orchiopexy the other one. If it was 1950 you’d call in your
nuclear medicine tech for scintigraphy. Now you just get a Doppler ultrasound. Findings will be
absent or asymmetrically decreased flow, asymmetric enlargement, and slightly decreased
echogenicity of the involved ball.
Paratesticular Rhabdomyosarcoma
By far the most common extra-testicular
mass in young men and the only one really worth mentioning. If you see a mass in the
scrotum that is not for sure in the testicle this is it (unless the history is kick to the balls from a
spiteful young lady - and you are dealing with a big fucking hematoma). If it’s truly a mass -
this is the answer.
Paratesticular Rhabdomyosarcoma
trivia
• The most common location is actually the head/neck - specifically the orbit and
nasopharynx.
• There is a bimodal peak (2-4, then 15-17).
Testicular Masses
Testicular Masses can be thought of as intratesticular or extratesticular. With regard to
intratesticular masses, ultrasound can show you that there is indeed a mass but there are no
imaging features that really help you tell which one is which. If the mass is extratesticular , the
most likely diagnosis is an embryonal rhabdomyosarcoma from the spermatic cord or epididymis
Testicular Mircolithiasis
This appears as
multiple small echogenic foci within the testes.
Testicular microlithiasis is usually an incidental
finding in scrotal US examinations performed for
unrelated reasons. It might have a relationship with
Germ Cell Tumors (controversial). Follow-up in 6
months, then yearly is probably the recommendation
(maybe - it’s very controversial, and therefore unlikely to be asked).
Testicular Cancer
Germ Cell (90%)
• Seminoma (40%) - seen more in the 4th decade
• Non Seminoma (60%)
• Teratoma, Yolk Sacs, Mixed Germ Cells, Etc.
Non Germ Cell (10%)
•Sertoli
•Leydig
THIS vs THAT:
Testicular
Calcifications
Tiny (micro) = Seminoma
BIG = Germ Cell Tumor
The two Germ Cell Tumors seen in the first decade of life are the
yolk sac tumor, and the
teratoma.
Yolk Sac Tumor
Heterogeneous Testicular Mass in < 2 year old = Yolk Sac Tumor. AFP is
usually super elevated.
Teratoma
Pure testicular teratomas are only seen in young kids < 2. Mixed teratomas are
seen in 25 year olds. Unlike ovarian teratoma, these guys often have aggressive biological behavior.
Choriocarcinoma:
An aggressive, highly vascular tumor, seen more in the 2nd decade.
Sertoli Cell Tumors
These testicular tumors are usually bilateral and are visualized on US
as “burned-out” tumors (dense echogenic foci that represent calcified scars). A subtype of Sertoli
cell tumor associated with Peutz-Jeghers syndrome typically occurs in children. If they show you
the Peurtz-Jegher lips and bilateral scrotal masses, this is the answer.
Testicular Lymphoma
Just be aware that lymphoma can “hide” in the testes because of
the blood testes barrier. Immunosuppressed patients are at increased risk for developing
extranodal/ testicular lymphoma. On US, the normal homogeneous echogenic testicular tissue is
replaced focally or diffusely with hypocchoic vascular lymphomatous tissue. Buzzword =
multiple hypoechoic masses of the testicle.
Sacrococcygeal Teratoma
This is the most common
tumor of the fetus or infant. These solid and/or cystic masses are
typically large and found either on prenatal imaging or birth.
Their largeness is a problem and can cause mass effect on the GI
system, hip dislocation, and even nerve compression leading to
incontinence. They are usually benign (80%), although those
presenting in older infants tend to have a higher malignant
potential. The location of the mass is either external to the pelvis
(47%), internal to the pelvis (9%), or dumbelled both inside and
outside (34%).
Sacrococcygeal Teratoma
types
The easiest way to remember it is like this:
- Type 1 - Totally extra pelvic
- Type 2 - Barely pelvic, but not abdominal
- Type 3 - Some abdominal
- Type 4 - Totally inside abdomen ** this one has the highest rate o f malignancy.
Sacrococcygeal Teratoma
trivia
They have to cut the coccyx off during resection. Incomplete resection of the coccyx is
associated with a high recurrence rate.
Fracture
In general, little kids bend they don’t break.
You end up with lots of buckles and greensticks. For
problem solving you can get a repeat in 7-10 days as
periosteal reaction is expected in 7-10 days. Kids tend to
heal completely, often with no sign of prior fracture.
Fracture
Involvement o f the Physis:
The major concern is growth
arrest, probably best asked by showing a physeal bar
(“early” bony bridge crossing the growth plate). You can
get bars from prior infection, but a history of trauma is
gonna be the more classic way to ask it.
Salter-Harris Classification
Type 1
S - Slipped
Complete physeal fracture, with or without
displacement.
Salter-Harris Classification
Type 2
A - Above (or “Away from the Joint”)
Fracture involves the metaphysis. This is the
most common type (75%).
Salter-Harris Classification
Type 3
L - Lower
(3 is the backwards “E ”fo r Epiphysis)
Fracture involves the epiphysis. These guys have
a chance of growth arrest, and will often require
surgery to maintain alignment
Salter-Harris Classification
Type 4
T - Through
Fracture involves the metaphysis and epiphysis.
These guys don’t do as well, often end up with
growth arrest, or focal fusion. They require
anatomic reduction and often surgery.
Salter Harris Classification
Type 5
R - Ruined
Compression of the growth plate. It occurs from axial loading injuries, and has a very poor
prognosis. These are easy to miss, and often found when looking back at comparisons (hopefully
ones your partner read). The buzzword is “bony bridge across physis”.
Toddler’s Fracture
Oblique fracture o f the midshaft o f the tibia seen in a child just
starting to walk (new stress on bone). If it’s a spiral type you probably should query nonaccidental
trauma. The typical age is 9 months - 3 years.
Stress Fracture in Children
This is an injury which occurs after repetitive trauma,
usually after new activity (walking). The most common site o f fracture is the tibia - proximal
posterior cortex. The tibial fracture is the so-called “toddler fracture” described above. Other
classic stress fractures include the calcaneal fracture - seen after the child has had a cast
removed and returns to normal activity.
The Elbow
Every first year resident knows that elevation o f the fat pad (sail sign) should make you think
joint effusion and possible occult fracture. Don’t forget that sometimes you can see a thin
anterior pad, but you should never see the posterior pad (posterior is positive). I like to bias
myself with statistics when I’m hunting for the peds elbow fracture. The most common
fracture is going to be a supracondylar fracture (>60%), followed by lateral condyle (20%),
and medial epicondyle (10%).
RadiocapiteUar Line
This is a line through the center of the radius, which should intersect the middle of the capitellum on every view (regardless of position). If the radius is dislocated it will NOT pass through the center of the capitellum
Anterior Humeral Line
This time you need a true lateral. A line along the anterior surface of humerus, should pass through the middle third of the capitellum. With a supracondylar fracture (the most common peds elbow fracture) you’ll see this line pass through the anterior third.
Ossification Centers are a
source of trickery.
elbow
Rr . emember they occur in a set order (c r it o e ) • Capitellum (Age 1) • Radius (Age 3), • Internal (medial epicondyle Age 5), • Trochlea (Age 7), • olecranon(Age 9), • External (lateral epicondyle Age 11).
Elbow Tricks
Lateral Condyle Fx
This is the second most common distal humerus fracture in kids.
Some dude named Milch classified them. The thing to know is a fracture that passes through
the capitello-trochlear groove is unstable (Milch II). Since it’s really hard to tell this,
treatment is based on the displacement of the fracture fragment (> or < 2mm).
Elbow Tricks
Trochlea
can have multiple ossification centers, so it can have a fragmented appearance
Elbow Tricks
Medial Epicondyle Avulsion (Little League Elbow
h e re are two major tricks
with this one. (1) Because it’s an extra-articular structure, its avulsions will not necessarily
result in a joint effusion. (2) It can get interposed between the articular surface of the
humerus and olecranon. Avulsed fragments can get stuck in the joint, even when there is no
dislocation.
Elbow Tricks
Nursemaids Elbow:
When a child’s arm is pulled on, the radial head may sublux into
the annular ligament. X-rays typically don’t help, unless you supinate the arm during lateral
position (which often relocates the arm).
Medial Epicondyle Avulsion (Little League Elbow
Anytime you see a dislocation - ask yourself
- Is the patient 5 years old ? And if so
* Where is the medial epicondyle ?
Medial Epicondyle Avulsion (Little League Elbow
The importance o f IT (crIToe)
• You should never see the trochlea and not see the
internal (medial epicondyle), if you do it’s probably a
displaced fragment
common elbow fracturess
lateral condylar
medial epicondyle
uncommon elbow fractures
lateral epicondyle
medial epicondyle
Avulsion Injuries
iliac cres
abdominal muscles
Avulsion Injuries
asis
sartorius
Avulsion Injuries
aiis
rectus femoris
Avulsion Injuries
greater trochanter
gluteal muscles
Avulsion Injuries
lesser trochanter
iliopsoas
Avulsion Injuries
ischial tuberosity
hamstrings
Avulsion Injuries
symphysis
adductor
Chronic Fatigue Injuries
Sinding-Larsen-Johansson
Osgood-Schlatter
Sinding-Larsen-Johansson
This is a
chronic traction injury at the insertion of the patellar
tendon on the patella. It’s seen in active adolescents
between age 10-14. Kids with cerebral palsy are
prone to it.
Osgood-Schlatter
This is due to repeated
micro trauma to the patellar tendon on its insertion at
the tibial tuberosity. It’s bilateral 25% of the time, and
more common in boys
Periosteal Reaction in the Newborn
Congenital Rubella Syphilis Caffey Disease Prostaglandin Therapy Neuroblastoma Mets Physiologic Growth Abuse
Congenital Rubella
Bony changes are seen in 50% of cases, with the classic buzzword
being “celery stalk” appearance, from generalized lucency of the metaphysis. This is usually
seen in the first few weeks o f life
Syphilis
Bony changes are seen in 95% of cases.
Bony changes do NOT occur until 6-8 weeks o f life
(Rubella changes are earlier). Metaphyseal lucent
bands and periosteal reaction along long bones can be
seen. The classic buzzword is “Wimberger Sign” or
destruction of the medial portion of the proximal
metaphysis of the tibia.
Caffey Disease
Have you ever seen that giant multiple volume set o f peds radiology
books? Yeah, same guy. This thing is a self limiting disorder of soft tissue swelling, periosteal
reaction, and irritability seen within the first 6 months of life. The classic picture is the
really hot mandible on bone scan. The mandible is the most common location (clavicle, and
ulna are the other classic sites). It’s rare as hell, and probably not even real. There have been
more sightings o f Chupacabra in the last 50 years.
Prostaglandin Therapy
Prostaglandin El and E2 (often used to keep a PDA open) can
cause a periosteal reaction. The classic trick is to show a chest x-ray with sternotomy wires (or
other hints of congenital heart), and then periosteal reaction in the arm bones.
Neuroblastoma Mets
This is really the only childhood malignancy that occurs in
newborns and mets to bones.
Physiologic Growth
So this is often called “Physiologic Periostitis of the Newborn” ,
which is totally false and wrong. It does NOT happen in newborns. You see this around 3
months of age, and it should resolve by six months. Proximal involvement (femur) comes
before distal involvement (tibia). It always involves the diaphysis.
Abuse
Some people abuse drugs, some just can’t stand screaming kids, some suffer both
shortcomings. More on this later.
It is NOT physiologic periostitis if:
- You see it before I month
- You see it in the tibia before the femur
- It does not involve the diaphysis.
Langerhans Cell Histiocytosis (LCH)
Also known as EG (eosinophilic
granuloma). It’s twice as common in boys. Skeletal manifestations are highly variable
Langerhans Cell Histiocytosis (LCH)
skull
Most common site. Has “beveled edge” from uneven destruction of the inner
and outer tables. If you see a round lucent lesion in the skull o f a child think this (and
neuroblastoma mets).
Langerhans Cell Histiocytosis (LCH)
ribs
Multiple lucent lesions, with an expanded appearance
Langerhans Cell Histiocytosis (LCH)
spine
Vertebra plana
Osteomyelitis
It usually occurs in babies (30% o f cases less than 2 years old). It’s usually hematogenous
(adults it directly spreads - typically from a diabetic ulcer).
There are some changes that occur over time, which are potentially testable.
Osteomyelitis
newborns
They have open growth plates and perforating vessels which travel from the
metaphysis to the epiphysis. Infection typically starts in the metaphysis (it has the most blood
supply because it is growing the fastest), and then can spread via these perforators to the
epiphysis.
Osteomyelitis
kids
Later in childhood, the perforators regress and the avascular epiphyseal plate stops
infection from crossing over. This creates a “septic tank” scenario, where infection tends to
smolder. In fact, 75% of cases involve the metaphyses o f long bones (femur most common).
Osteomyelitis
adults
When the growth plates fuse, the barrier of an avascular plate is no longer present,
and infection can again cross over to the epiphysis to cause mayhem.
Osteomyelitis
trivia
- Hematogenous spread more common in kids (direct spread in adult)
- Metaphysis most common location, with target changes as explained above
- Bony changes don’t occur on x-ray for around 10 days.
- It’s serious business and can rapidly destroy the cartilage if it spreads into the joint
Short Fingers
Brachydactyly
Too Many Fingers
Polydactyly
Two or More Fused Fingers
“Sock Hand” - 1 call it
Syndactyly
Contractures o f Fingers
Camptodactyly
Radially Angulated Fingers (Usually 5,h)
Clinodactyly
Long, Spider-Like Fingers
Arachnodactyly
Limb is Absent
Amelia
Limb is mostly Absent
Meromelia
Hands / Feet (distal limbs) are Short
Acromelic
Forearm or Lower Leg are short (middle limbs)
Mesomelic
Femur or Humerus (proximal limbs) are short
Rhizomelic
Short All Over
Micromelic
Achondroplasia
This is the most common skeletal dysplasia, and is the mostly likely
to be seen at the mall (or on television). It results from a fibroblast growth factor receptor
problem (most dwarfisms do). It is a rhizomelic (short femur, short humerus) dwarf. They
often have weird big heads, trident hands (3rd and 4th fingers are long), narrowing o f the
interpedicular distance, and the tombstone pelvis. Advanced paternal age is a risk factor.
They make good actors, excellent rodeo clowns, and various parts o f their bodies (if cooked
properly) have magical powers.
Thanatophoric
This is the most common lethal dwarfism. They have rhizomelic
shortening (humerus, femur). The femurs are sometimes called telephone receivers. They
have short ribs and a long thorax, and small iliac bones. The vertebral bones are flat
(platyspondyly), and the skull can be cloverleaf shaped
Asphyxiating Thoracic Dystrophy (Jeune)
This is usually fatal as well. The
big finding is the “Bell shaped thorax” with short ribs. 15% will have too many fingers
(polydactyly). If they live, they have kidney problems (chronic nephritis). You can
differentiate a dead Thanatophoric dwarf, from a dead Jeune dwarf by looking at their
vertebral bodies. The Jeune bodies are normal (the thanatophorics are flat).
•Ellis-Van Crevald
is the dwarf with multiple fingers.
•Pseudoachondroplasia
is this weird thing not present at birth, and spares the skull.
Pyknodysostosis
osteopetrosis, in a dwarf with a wide angled jaw, & Acro-osteolysis
The Dwarf Blitz - 5 Things I Would Remember About Dwarfs
- The Vocab: Rhizo (humerus, femur) vs Aero (hands, feet) vs Meso (forearm, tib/fib)
- Most dwarfs are Rhizomelic - if forced to choose, always guess this
- The pedicles are supposed to widen slightly as you descend the spinal column,
Achondroplasia has the opposite - they narrow. If you see a live dwarf, with short
femurs / humerus, and narrowing of the pedicles then this is the answer.
(technically thantophorics can get this too - but it s more classic fo r achondroplasia) - Thanatophoric is your main dead dwarf. Usually the standout feature is the
telephone receiver femur (and a crazy cloverleaf head) - Jeune is another dead dwarf - but the short ribs really stand out.
Bifid Rib
This is the most common cause of an anterior wall “mass.” If there is just one (usually
the 4th rib) - then it is just a variant. If there are bunches think Gorlin Syndrome.
Gorlin Syndrome
Bifid Ribs, Calcifications of the Falx, basal cell cancers, odontogeni keratocysts (lytic jaw lesions).
Osteogenesis Imperfecta
They have a collagen defect and make brittle bones. Depending
on the severity it can be totally lethal or more mild. It’s classically shown with a totally lucent skull,
01 multiple fractures with hyperplastic callus. Another classic trick is to show the legs with the
fibula longer than the tibia. They have wormian bones, and often flat or beaked vertebral bodies.
Other trivia is the blue sclera, hearing impairment (otosclerosis), and that they tend to suck at football.
Osteopetrosis
They have a defect in the way osteoclasts work, so you end up with
disorganized bone that is sclerotic and weak (prone to fracture). There are a bunch of different types,
with variable severity. The infantile type is lethal because it takes out your bone marrow. With less
severe forms, you can have abnormal diminished osteoclastic activity that varies during skeletal
growth, and results in alternating bands of sclerosis parallel to the growth plate. Most likely the way
this will be shown is the “bone-in-bone” appearance in the vertebral body or carpals. Picture frame
vertebrae is another buzzword. Alternatively, they can show you a diffusely sclerotic skeleton, with
diffuse loss of the corticomedullary junction in the long tubular bones.
Pyknodysostosis
Osteopetrosis + Wormian Bones + Acro-Osteolysis. They also
have “wide (or obtuse) angled mandible ”, which apparently is a buzzword.
Klippel Feil
You get congenital fusion of the cervical spine (sorta like JRA).
The cervical vertebral bodies will be tall and skinny. There is often a sprengel deformity
(high riding scapula). Another common piece of trivia is to show the omovertebral bone
- which is just some big stupid looking vertebral body.
Hunters I Hurlers / Morquio
All three of these are mucopolysaccharidoses. Findings
include oval shaped vertebral bodies with anterior beak. The beak is actually mid in Morquio, and
inferior in Hurlers. Clavicles and ribs are often thick (narrow more medially) - like a canoepaddle.
The pelvis shape is described as the opposite of achondroplasia - the iliac wings are tall and
Haired. The hand x-ray is the most commonly shown in case books and gives you wide metacarpal
bones with proximal tapering.
Few More Trivia Points on Morquio
- They are dwarfs
- The most common cause of death is cervical myelopathy at C2
- The bony changes actually progress during the first few years of life
Neurofibromatosis
Just briefly remember that type 1
can cause anterior tibial bowing, and pseudarthrosis at the
distal tibula.
This is an Aunt Minnie.
They often have scoliosis. Just think of the elephant man
Gauchers
This is the most common lysosomal storage
disease. It gives you a big spleen, and big liver among a few
bone signs.
*A VN o f the Femoral Fleads
• FI-Shaped Vertebra
• Bone Infarcts (lots o f them)
•Erlenmeyer Flask Shaped Femurs
Caudal Regression Syndrome
This is a spectrum
that includes sacral and/or coccyx agenesis. You see it with
VACTERL and Currarino Triads Syndromes.
Scoliosis
Lateral curvature of the spine, which is usually idiopathic in girls. It can also be from
vertebral segmentation problems. NF can cause it as well (that’s a piece of trivia).
Radial Dysplasia
Absence or hypoplasia of the radius (usually with a missing thumb) is a differential case (VACTERL, Holt-Oram, Fanconi Anemia, Throbocytopenia Absent Radius). As a point of trivia TAR kids will have a thumb.
Hand Foot Syndrome
The classic history is hand or
foot pain / swelling in an infant with sickle cell. This is a
dactylitis, and felt to be related to ischemia. It will resolve on
its own, after a few weeks. Radiographs can show a
periostitis two weeks after the pain goes away.
Blounts
tibia vara). Varus angulation occurring at the
medial aspect of the proximal tibia (varus bowing occurs at
the metaphysis not the knee). This is often bilateral, and
NOT often seen before age 2 (two sides, not before two).
Later in the disease progression the medial metaphysis will
be depressed and an osseous outgrowth classically develops.
You can see it in two different age groups; (a) early - which
is around age 2 and (b) late - which is around age 12.
Two Sides - Not Before Two
Two Different Ages (2-3, 12)
Talipes
Congenita
Pes
Foot or Acquired
Equines
Plantar Flexed Ankle ”, Heel Cord is often tight, and the heel won’t touch the floor
Calcaneus
Opposite o f Equines. The Calcaneus is actually angled up
Varus
Forefoot in
Valgus
Forefoot out
Cavus
High Arch
Planus
Opposite o f Cavus - “bizarro cavus” - FLAT FOOT
Supination
Inward rotation - “Sole offoot in ” - holding soup with the bottom o f your foot
Pronation
Outward rotation - “Sole offoot out”
Hindfoot Valgus
Think about this as the talus sliding nose down off the calcaneus. This make the angle wider. If the talus slides off you lose your longitudinal arch - which essentially characterizes hindfoot valgus. Also, note that the nose down (nearly vertical) appearance of the talus . “Too Many Toes”
Talocalcaneal angle
hindfoot varus: <25°
normal: 25-40°
hindfoot valgus: >40°
Hindfoot Varus
This is the opposite situation, in which you have a narrowing of the angle between the talus and calcaneus. Notice the two bones lay nearly parallel - like two “clubs” laying on top of each other.
Flat Foot (Pes Planus)
This can be congenital or acquired. The peds section will cover
congenital and the adult MSK section will cover acquired. The congenital types can be grouped into
flexible or rigid (the flexible types are more common in kids). The distinction can be made with
plantar flexion views (flexible improves with stress). The ridged subtypes can be further subdivided
into tarsal coalition and vertical talus. In any case you have a hindfoot valgus
Tarsal Coalition
There are two main types (talus to the calcaneus, and calcaneus to the
navicular). They are pretty equal in incidence, and about 50% o f the time are bilateral. You
can have bony or fibrous/cartilaginous subtypes. The fibrous/cartilaginous types are more
common than the bony types.
Tarsal Coalition
Talocalcanea
Occurs at the middle facet.
Has the “continuous C-sign ” produced from an “absent middle fac et” on
the lateral view. Talar beak (spur on the anterior talus - white arrow) is also
seen in about 25% of cases.
Tarsal Coalition
Calcaneonavicula
Occurs at the anterior facet.
Has the “anteater sign ” Where the elongated anterior process o f the
calcaneus resembles the blood thirsty nose of a ravenous ant eater. This
is best seen on an oblique view.
Vertical Talus
(equinus hindfoot valgus) - This is
sometimes called the “rocker-bottom foot” because the talus is
in extreme plantar flexion with dorsal dislocation of the
Navicular - resulting in a locked talus in plantar flexion. As a
point of trivia this is often associated with myelomeningocele
Club Foot (Talipes Equino Varus)-
Translation - Congenital Plantar Flexed Ankle
Forefoot. This is sorta why I lead with the vocab, all the congenital feet can be figured out based on
the translated language. This thing is more common in boys, and bilateral about half the time. The
toes are pointed down (equines), and the talocalcaneal angle is acute (varus).
Club Foot (Talipes Equino Varus)-
key findings
* Hindfoot varus (decreased talocalcaneal angle) * Medial deviation and inversion of the forefoot * Elevated Plantar Arch
Club Foot (Talipes Equino Varus)-
trivia
The most common surgical complication is over correction resulting in a “rocker bottom” flat foot deformity.
Developmental Dysplasia of the Hip
overview
This is seen more commonly in females,
children bom breech, and oligohydramnios. The physical exam buzzwords are asymmetric
skin or gluteal folds, leg length discrepancy, palpable clunk, or delayed ambulation. It’s
bilateral about 1/3 of the time. Ultrasound is done to evaluate (after physical exam), and is
excellent until the bones ossify (then you need x-rays). A common trick is to be careful
making a measurement in the first week o f life - the laxity immediately after birth (related to
maternal estrogen) can screw up the measurements.
Developmental Dysplasia of the Hip
angles us
On ultrasound the alpha angle, should be
more than 60 degrees. Anything less
than that and your cup is not deep enough
to hold your ball. The plain film
equivalent in the acetabular angle, which
is the complimentary angle (and
therefore should be less than 30).
Developmental Dysplasia of the Hip
angles, getting them confused
Remember that the “Alpha Angle is the Alpha Male’’ - and therefore the bigger of the two angles. **But don’t forget that DDH is more common in women (not alpha males).
Developmental Dysplasia of the Hip
acetabular angle
The acetabular angle should decrease from 30 degrees at birth to 22 degrees at age 1. DDH is the classic cause o f an increased angle, but neuromuscular disorder can also increase it.
Developmental Dysplasia of the Hip
position of the femoral epipysis
The position of the femoral epiphysis (or where it will be) should be below Hilgenreiner’s line “H”, and medial to Perkin’s Line “P”. Shenton’s Line “S” should be continuous.
Proximal Focal Femoral Deficiency
This is a congenital zebra,
which ranges from absent proximal femur to hypoplastic proximal femur. You
get a varus deformity. This is a mimic o f DDH, but DDH will have normal
femur leg length.
Slipped Capital Femoral Epiphysis (SCFE)
This is a type 1 Salter Harris,
through the proximal femoral physis. What makes this unique is that unlike most SH Is, this
guy has a bad prognosis if not fixed. The classic history is a fat African American
adolescent (age 12-15) with hip pain. It’s bilateral in 1/3 o f cases (both hips don’t usually
present at same time). The frog leg view is the money - this is always the answer on next step questions.
Legg-Calve-Perthes
This is AVN of the proximal femoral epiphysis. It’s seen more in
boys than girls (4 :1 ), and favors white people around age 5-8. These kids tend to be smaller
than average for their age. This is bilateral about 10% of the time (less than SCFE). The
subchondral lucency (crescent sign) is best seen on a frog leg. Other early signs include an
asymmetric small ossified femoral epiphysis. MRI has more sensitivity. The flat collapsed
femoral head makes it obvious. Sterile joint effusions (transient synovitis) can be associated
“Klein’s Line”
Drawn along the edge of the
femur and should normally intersect with lateral
superior femoral epiphysis. This line is used to
evaluate for SCFE. When the line doesn’t cross
the lateral epiphysis think SCFE.
***Testable Trivia - Frog Leg View is more
sensitive for this measurement
Perthes quick
often small white kids
ages 5-8
bilateral 10%
SCFE quick
overweight black kids
age 12-15
bilateral 30%
Septic Arthritis
This is serious
business , and considered the most urgent
cause o f painful hip in a child. Wide joint
space (lateral displacement of femoral head),
should prompt an ultrasound, and that should
prompt a joint tap. If you have low suspicion
and don’t want to tap the hip, You could pull
on the leg under fluoro and try and get gas in
the joint. This air arthrogram sign supposedly
excludes a joint effusion (and therefore a
septic joint) - depending on who you ask.
Transient Synovitis
This is a sterile
(reactive) hip effusion that occurs in the
setting of a systemic illness (usually viral
UR1 or GI). As the name suggests this is
“transient” and goes away in a few days.
This is actually very common. Some
sources will say its the most common hip
disorder in growing children (peak age is
around 5). The ED will be in a full panic and
want you to tap it at 3 am.
THIS vs THAT: Transient Synovitis vs Septic Arthritis
overview
Telling these apart is actually important for real life (not getting sued) since a septic hip will
fucking destroy the kid’s cartilage (usually if it’s missed for more than 4 days).
Ortho (and in very rare situations a “smart” ED doc)
will use a clinical parameter “the Kocher Criteria ” to
tell them apart.
THIS vs THAT: Transient Synovitis vs Septic Arthritis
kocher criteria
• Fever
• Inability to walk
• Elevated ESR (or CRP)
. WBC > 12K
THIS vs THAT: Transient Synovitis vs Septic Arthritis
bullets
• If 3/4 are positive = Septic • If CRP is negative and the kid can bear weight it’s NOT Septic • CRP is the strongest independent risk factor for septic arthritis
THIS vs THAT: Transient Synovitis vs Septic Arthritis
typical workup
- X-Ray Hip series (AP, Lateral, and Frog Leg) which is usually negative in real life but
will probably show medial joint widening on the exam. - Ultrasound which will show an effusion.
- Then a clinical decision based on Kocher Criteria (>2) and “Gut Instinct” to Aspirate
- MRI would only be used if/when hip aspiration can’t/hasn’t been performed
Rickets
Not enough vitamin D. Affects the most
rapidly growing bones (mostly knees and wrists).
Buzzwords “fraying, cupping, and irregularity along
the physeal margin. ” They are at increased risk for
SCFE. “Rachitic rosary” appearance from expansion of
the anterior rib ends at the costochondral junctions. As a
pearl, rickets is never seen in a newborn (Mom’s
vitamin D is still doing its thing).
Hypophosphatasia
This looks like Rickets in a
newborn. They will have frayed metaphyses and bowed
long bones. The underlying pathology is deficient
serum alkaline phosphatase. There is variability in
severity with lethal perinatal / natal forms, and more mild
adult forms.
Scurvy
Not enough vitamin C. This is rare as hell outside o f a pirate ship in the 1400s.
For the purpose of trivia (which multiple choice tests love) the following stuff is high yield:
* Does NOT occur before 6 months o f age (maternal stores buffer)
o Bleeding Disorders Common
o Subperiosteal hemorrhage (lifts up the periosteum)
* Hemarthrosis
* “Scorbutic rosary” appearance from expansion of the costochondral junctions (very
similar to rickets).
Lead Poisoning
This is most commonly seen in kids less than two who eat paint chips.
The classic finding is a wide sclerotic metaphyseal line (lead line), in an area o f rapid
growth (knee). It will not spare the fibula (as a normal variant line might).
Lucent Metaphyseal Bands
- This is a classic peds DDx. - LINE.
- Leukemia
- Infection (TORCH)
- Neuroblastoma Mets
- Endocrine (rickets, Scurvy)
Non-Accidental Trauma I NAT
Posterior Medial Rib Fracture
Metaphyseal Corner Fractures
Skull Fracture
Solid Organ and Lumen Injury
Posterior Medial Rib Fracture
In a child under the age o f
3, this is pretty reliable. Supposedly this type o f fracture can
only be made from squeezing a child.
Metaphyseal Corner Fractures
When this is present in a
non-ambulatory patient (infant) it is HIGHLY specific. The
only exception is obstetric trauma. After age 1, this becomes
less specific.
Skull Fracture
The general idea is anything other than a parietal bone fracture (which is
supposedly seen more with an actual accident) is concerning.
Solid Organ and Lumen Injury
Don’t forget about this as a presentation for NAT.
Duodenal hematoma and pancreatitis (from trauma) in an infant - should get you to say
NAT. Just think “belly trauma in a kid that is too young to fall on the handle bars o f their
bike
Dating the Fracture:
• Periosteal Reaction: This means the fracture is less than a week old.
• Complete healing: This occurs in around 12 weeks.
• Exceptions: Metaphyseal, skull, and costochondral junction fractures will often heal
without any periosteal reaction.
C hild A b u s e M im ic s
Rickets and 0 1 , can have multiple fractures at different sites and are the two most
commonly described mimics.
Wormian bones and bone mineral density issues are clues that you are dealing with a
mimic. They will have to show you one or the other (or both) if they are gonna get
sneaky.
Central Canal
Easily identified as an
echogenic line. Although that is sort o f counter
intuitive.
Central Canal Why would a structure with fluid in it be
echogenic?
The reason is that you are actually
seeing a “central echo complex” - which is the
interface between the anterior median fissure and
the myelinated ventral white matter commissure.
Remember that interfaces between things with
large differences in impedance cause a lot of
reflections (thus an echogenic line).
Central Canal
trivia
Technically in a newborn the central canal is not even fluid filled (it’s packed with
glial fibrils), but that level of trivia is beyond the scope o f the exam (probably).
Low lying cord I Tethered cord
Because the canal grows faster than the cord, a
fixed attachment (“tethering”) results in cord stretching and subsequent ischemia. This can be
primary (isolated), or secondary (associated with myelomeningocele, filum terminale lipoma,
or trauma). The secondary types are more likely shown on MR (to showcase the associated
mass - fluid collection), the primary types are more likely shown on US - as a straight
counting game.
Low lying cord I Tethered cord
imaging features
Low conus (below L2L and thickened filum terminale (> 2mm).
Low lying cord I Tethered cord
high yeild trivia
A common piece o f trivia used as a distractor is that meningomyelocele is associated with
Chiari malformations, lipomyelomeningocele is NOT.
- Anal Atresia = High Risk For Occult Cord Problems (including tethering) - should get
screened - Low lying / tethered cords are closely linked with Spina Bifida (tufts o f hair)
- Low Dimples (below the gluteal crease) Do NOT need screening,
o These never extend intra-spinally. They might later become a pilonidal sinuses - but aren’t ever gonna have shit to do with the cord.
- High Dimples (above the gluteal crease) DO need screening.
Low lying cord I Tethered cord
for screening
Low dimples (below the butt crease) don’t get screened, basically everything else does. Most Likely Question Style: “Which of the following does NOT get screened ?” (Answer = low dimple).
Terminal Ventricle (ventriculus terminalis):
This is a developmental variant.
Normally, a large portion o f the distal cord involutes in a
late stage of spinal cord embryology. Sometimes this
process is not uniform and you get stuck with a stupid
looking cyst at the end o f your cord. These things are
usually small (around 4 mm), and cause no symptoms.
Sometimes they can get very big (like this example) and
cause some neurologic symptoms.
Pars Interarticularis Defects (Spondylolysis
This is considered a fatigue or stress fracture, probably developing in
childhood. It is a classic cause o f back pain in an adolescent athlete.
Although they are usually not symptomatic (only 25% are). The
process represents a hole / break in the connecting bone between the
superior and inferior articular facets. If there is forward “slippage”
you can deploy the word spondylolisthesis.
Almost always (90% +) you see this at L5 (2nd most common at L4).
They tend to have more spondylolisthesis and associated degenerative
change at L4-L5 than L5-S1. They can be seen on the oblique plain
film as a “collar on the scottie dog.” The collar on the “scotty dog”
appearance on an oblique plain film is probably the most common
way they show this in case books and conferences. On the AP view
this can be a cause o f a sclerotic pedicle (the contralateral pedicle -
from wiggle stress). On CT it is usually more obvious with the break
clearly demonstrated.
**Pars Defects with anterolisthesis will have neuroforaminal stenosis,
with spinal canal widening (when severe will have spinal canal
stenosis as well). If the process is purely a degenerative
spondylolisthesis (not much slippage), the resulting facet arthropathy
will favor the canal with less severe effects on the neuro foramina
Spinal Dysraphism
You can group these as open or closed (closed with and without a mass). Open means neural
tissue exposed through a defect in bone and skin (spina bifida aperta). Closed means the
defect is covered by skin (spina bifida occulta).
Open Spinal Dysraphisms
This is the result o f a failure o f the closure of the primary
neural tube, with obvious exposure o f the neural placode through a midline defect o f the skin.
You have a dorsal defect in the posterior elements. The cord is going to be tethered. There
is an association with diastematomyelia and Chiari II malformations. Early surgery is the
treatment / standard of care.
Open Spinal Dysraphisms
Myelocele
This is the more rare type where the neural
placode is flush with the skin.
Open Spinal Dysraphisms
Myelomeningocele
This is the more common type
(98%) where the neural placode protrudes above the
skin. These are more common with Chiari II
malformations.
Closed Spinal Dysraphisms with Subcutaneous Mass
Meningocele
This is herniation o f a CSF filled sac through a
defect in the posterior elements (spina bifida). It is most typical
in the lumbar or sacral regions. Although they can occur in the
cervical spine. They may be anterior (usually pre-sarcral). An
important point is that neural tissue is NOT present in the
sac.
Closed Spinal Dysraphisms with Subcutaneous Mass
Lipomyelocele / Lipomyelomeningocele
These are lipomas with a dural defect. On
exam you are going to have a subcutaneous fatty mass above the gluteal
crease. These are 100% associated with tethered cord
(myelomeningocele may or may not).
Closed Spinal Dysraphisms with Subcutaneous Mass
Terminal Myelocystocele
This is a herniation o f a terminal
syrinx into a posterior meningocele via a posterior spinal defect
Closed Spinal Dysraphisms without Subcutaneous Mass
Intradural lipomas
Most common in the thoracic spine along the dorsal aspect.
They don’t need to be (but can be) associated with posterior element defects.
Closed Spinal Dysraphisms without Subcutaneous Mass
Fihrolipoma o f thefilum terminate
This is often an incidental finding “fatty filum”.
There will be a linear T1 bright structure in the filum terminale. The filum is not
going to be unusually thickened and the conus will be normally located.
Closed Spinal Dysraphisms without Subcutaneous Mass
Tight filum terminale
This is a thickened filum terminale (> 2 mm), with a low lying
conus (below the inferior endplate of L2). You may have an associated terminal lipoma.
The “tethered cord syndrome” is based on the clinical findings o f low back pain and leg
pain plus urinary bladder dysfunction. This is the result o f stretching the cord with
growth o f the canal.
Closed Spinal Dysraphisms without Subcutaneous Mass
Dermal Sinus
This is an epithelial lined tract that extends from the skin to deep soft
tissues (sometimes the spinal canal, sometimes a dermoid or lipoma). These are T1 low
signal (relative to the background high signal from fat).
Diastematomyelia
This describes a sagittal split in the spinal cord. They almost always
occur between T9-S1, with normal cord both above and below the split. You can have two thecal
sacs (or just one), and each hemi-cord has its own central canal and dorsal/ventral horns.
Classification systems are based on the presence / absence o f an osseous or fibrous spur and
duplication or non-duplication o f the thecal sac.
Caudal Regression
This is a spectrum o f defects in the caudal region that ranges from
partial agenesis o f the coccyx to lumbosacral agenesis. The associations to know are VACTERL
and Currarino triad. Think about this with maternal diabetes. “Blunted sharp” high terminating
cord is classic, with a “shield sign” from the opposed iliac bones (no sacrum).
Caudal Regression
trickery
Note than the Meningocele of
Currarino is Anterior. It’s not posterior. A
potential deployment o f fuckery is to put
“Posterior” Sacral Meningocele as a
distractor for Currarino Triad.
Currarino Triad
Anterior Sacral Meningocele, • • •• • • Anorectal malformation, Sacrococcygeal osseous defect (scimitar sacrum).
