Random_6 Flashcards
Primary vs Secondary TB
- Primary TB - consolidation, LAD, pleural effusion
- Secondary TB - upper lung zone, cavitation
Giant hepatic hemangioma
- > 4cm in diameter
- can be complicated by acute hemorrhage - acute abdominal pain, lesion enlargement, hyperdense foci on CT, hyperintense T1 and hypointense rings/bands on T2
Chiari malformation
- Chiari I malformation
- underdeveloped posterior fossa
- normal sized cerebellum tries to fit in –> inferior tonsillar herniation
- children > 7mm
- adults > 5mm
- CSF outflow obstruction at the level of foramen magnum
- Rx - sx decompression to restore and maintain CSF flow
- Chiari II malformation
- associated with midline abnormality and neural tube defect - myelomeningocele
West Nile Virus
- WNV can cause a poliomyelitis-like syndrome with acute flaccid paralysis of the extremities typically with sensory sparing.
MRI of the spine will often appear normal but in some instances may demonstrate enhancement of the anterior horn or ventral nerve roots. - Enhancing ventral nerve roots on MRI is a relatively nonspecific finding and may be seen in a number of other conditions aside from WNV including, DDx
- Guillain-Barre syndrome
- meningitis
- neurosarcoidosis
Where does inferior alveolar nerve run?
Within the mandibular canal.
Exits through the mental foramen anteriorly.
Anatomy of the mandible

DISH
Actually ossification of the
anterior longitudinal ligament
and maybe
posterior longitudinal ligament (OPLL)
WITH OR WITHOUT osteophytes
What to do when you are unsure whether something is truely SDH or just brain parenchyma cut-through funny?
Repeat the study!
Hopefully by then the cut will be different and you can tell!!
Ewing sarcoma
- age of onset - most common 11-15y/o, vast majority <15 y/o
- compared to osteosarcoma 10-25 y/o
- most common location - pelvis
- the most common malignancy arising from the ribs in pediatric patients - Ewing sarcoma
What drug gives you tracheobronchial calcification?
Warfarin
MM patients can have what kind of nodules in the lungs?
Amyloid
How do you differentiate pericardial from myocardial calcifications?
- Pericardial calcification - along the RV, AV grooves
- Myocardial calcification - along the LV

In-utero bowel perforation
from meconium
meconium peritonitis


- 3 stages:
- early lytic phase (hot on bone scan),
- intermediate or mixed phase,
- osteoblastic or cold phase (minimal activity or normal bone activity on bone scan)
- Bone scans are more sensitive than radiographs and help define extent of disease, since most patients have more than one bone involved
- Typical appearance of Paget’s disease in long bone –> starts at the end of the bone and advances along shaft of the bone expanding the cortex!!! almost always starts at the epiphysis!!! (“candle flame”, “blade of grass”)
- 1% undergo sarcomatous degeneration - other complications would include pain, insufficiency fractures, compressive neuropathy
- Etiology: Unknown, but possibly connected to parvomyxovirus, environmental factors
Typical MR appearance of AVN

- T2 or PD hyperintense - hyperemia and granulation tissue
- T1 hypointense margin - linear sclerosis

Patellar chondromalacia
aka
Patellar tendon - lateral femoral condyle friction syndrome
aka
Hoffa’s fat pad impingement syndrome
- anterior knee pain, esp climbing stairs
- grading
- I - softening and swelling
- II - fissuring
- III - less than full depth
- IV - full depth, exposing subchondral bone
- associated with patellar maltracking, e.g., patellar alta
- T2 hyper in the Hoffa’s fat pad; fraying of the apical and lateral patellar cartilage
Most common acquired deafness in children
- labyrinthine ossificans
- ossification of membranous labyrinth
- complications of OM or meningitis
- hazy foggy appearance of bones
- loss of signal on MR

Indications for breast MR
- staging for Rx plannig - masectomy vs lumpectomy
- indeterminate lesion on Mammo or US, and when breast bx is cannot be done
- dense breasts (not proven yet)
- axillary node with unknown primary - negative mammogram/US
- restage post-Rx
- high risk screening
Most important sequences for breast MR
Dynamic acquisition
- steady - normal
- plateau - indeterminate
- washout - bad
other features that are worrisome for malignancy
- spiculated borders
- peripheral enhancement
- regional/blotchy enhancement
- ductal enhancement
Which patients are considered high risk for breast cancer?
- risk > 20%
- BRCA-1/2 - starts screening 10 years before diagnosis of the index relative
- childhood radiation - starts screening 8 years after radiation
Spindle cell…
is a buzz word for … ?
Sarcoma
Sarcomatoid tumors
DDx for VERY fast growing tumor in the chest
- sarcoma
- lymphoma
I-131 uptake may be physiologic in
- IUD
- Uterine fibroids
Carney syndrome
- extra-adrenal paragangliomas
- GIST
- pulmonary chondroma/hamartomas
What is MIBI?
Lipophilic cation
Attacted to mitochondria
Pertechnetate
- TcO4-
- attached to Tc99m - water solube compound
- b/c it is negatively charged anion, can replace I- in NaI / I123 in thyroid imaging - only measures thyroid uptake, not organification
- also used in
- thyroid scan
- RBC/MUGA scan
- splenic tissue
- Meckel’s scan - actively accumulated and secreted by gastric mucosa
Pulmonary vasculitides and serum markers
- Wegeners granulomatosis - C-ANCA
- Churg-Strauss syndrome - P-ANCA
- Goodpasture’s - anti-GBM Ab
Distribution of Goodpastures alveolar hemorrhage?
- bilateral
- perihilar
- relative apical sparing
- bimodal age distribution
Opacity
vs
Opacification
- Opacity - when you can count 1,2, or 3 opacities
- Opacification - use it when you have diffuse opacification and not numerable
Calcification of vas deferens?
Diabetes
What are the most two common causes of mycetomas?
- Old TB cavity
- Sarcoid cavity
Mycetoma
vs
Angioinvasive aspergilloma
Completely different entities!!!
Mycetoma
- fungus ball occupying pre-existing cavities from TB or sarcoid
- no surrounding GGO
- may bleed, not b/c it’s angioinvasive, but b/c neovasculature friable and tend to bleed
- Monod sign
Angioinvasive asperigilloma
- no need for pre-existing cavities
- lung consolidations with surrounding GGO - halo sign
- centrally necrotic lung pulling inward - air crescent sign
When does V1 enter and exit the orbit?
- Enter: through the superior orbital fissure
- Exit: through the supra-orbital foramen

Collaterals to the vertebral artery
- ECA branches - occipital artery branches
- SCA branches
- thyrocervical trunk
- inferior thyroid artery
- anterior cervical artery
Swyer-James Syndrome

- obliterative bronchiolitis triggered by certain infections prior to lung maturity (<8y/o)
- adenovirus (most common)
- mycoplasma
- TB
- bordatella pertussis
- measles
- RSV
- hypoplastic pulmonary artery with an associated small lung/lobe/segment
- hyperinflation of the uninvolved lung***
- most asymptomatic, children may present with recurrent infections

DDx for unilateral hyperlucent lung
- extra-pulmonary
- Poland syndrome
- mastectomy
- thoracic
- pneumothorax
- pulmonary
- vascular
- PE
- airway
- foreign body
- congenital lobar emphysema
- compensatory - pathology is on contralateral side
- prior pneumonectomy
- Swyer James
- pulmonary agenesis
- vascular
How to tell a ureteric stone on US?
- highly echogenic
- posterior shadowing
- twinkling artifact on doppler US
- generated by a random strong reflection and
multiple inner reflections of the incidental US beam at a rough interface formed
by a crystalline aggregate of stones
- generated by a random strong reflection and
Normal diameter of panncreatic duct
3-2-1
Sarah Kelly’s pet peeves
- DON’T say right-sided or left-sided; SAY right or left
- DON’T use note is made of, noted too often; mix it up; say there is…
- LIMIT the use of “appears”
- DON’T repeat HEPATIC/RENAL cysts often
- “STATISTICALLY represent renal/hepatic cysts”
Lissencephaly

- neuronal migration disorder
- due to genetic mutation OR in utero insult
- Ch 17
- CMV infxn is a common cause
- arrest of neuronal migration –> sparse white matter; poorly developed corticospinal tracts
- developmental delay & seizures
- imaging features
- diffuse cortical thinning
- poor formation of cortical gyri - pachygyri
- sparse white matter –> compensatory dilatation of lateral ventricles
- no contrast enhancement
- if related to CMV infxn, may have subcortical calcification
- band heterotopia
- a type of lissencephaly
- a symmetric band of gray matter embedded within WM

Causes of cavities in the lungs
- most often due to necrosis from infections such as TB or Staph aureus, or inflammations such as sarcoidosis
- central necrosis –> some communication with the remainder of the lung/airway –> air containing cavities
- gas forming organism causing air containing abscess is very rare in the lungs
- vs gas forming organism causing abscesses is more common in the abdomen!
Bronchopleurla fistula
- 2 types of communication b/t pleural space and airways
- bronchopleural fistula - b/t pleural space and large bronchi
- parenchymal-pleural fistula - b/t pleural space and distal airways
- causes of bronchopleural fistula
- thoracic surgery
- radiation
- malignancy
- necrotizing pneumonia
- normal post-op from pneumonectomy
- immediate post op - an air-fluid level is typical present
- over time, the air decreases, and pleural space is filled with fluid
- if there is a BP fistula post pneumonectomy
- air increases over time
- fluid decreases over time
- drop in the level of AF level
Galeazzi fracture
vs
Monteggia fracture

- Galeazzi fracture
- fall on outstretched hand
- fracture of distal radius
- dislocation of distal ulna or DRUJ
- Monteggia fracture
- nightstick fracture
- fracture of proximal ulna
- distal location of radial head

Profound MCP subluxation
but lack of erosive changes
Lupus arthritis
What is a characterstic feature of
exostosis/osteochondroma?
contiguous with the medullary cavity
due to growth plate disturbance
Signs of tarsal coalition
- C-sign
- talar beak sign/ anteater sign
Osteosarcoma
- second most common malignant bone tumor (following multiple myeloma)
- classification
- primary
- < 20y/o
- metaphysis of long bones
- secondary
- elderly
- associated with paget’s, radiation, bone infarcts, chronic OM etc
- flat bones - pelvis (paget’s)
- primary
Subtypes of osteosarcoma
- intramedullary osteosarcoma - 80%
- conventional high-grade osteosarc - most common
- telangiectatic osteosarcoma
- low-grade osteosarcoma
- surface osteosarcoma - 10-15%
- intra-cortical osteosarcoma
- parosteal osteosarcoma
- periosteal osteosarcoma
- extra-skeletal osteosarcoma - 5%
- extra-skeletal osteosarcoma

Telangiectatic osteosacoma

- 2.5-12% of all osteosarcomas
- adolescents and young adults
- male > female
- telangiectatic component > 90% of the tumor - blood filled spaces seprated by thin bony septations
- imaging
- fluid-fluid levels with different signal intensity on MR

Parosteal sarcoma

- a type of surface osteosarcoma
- early adulthood and middle age
- most common location
- posterior surface of distal femur
- a dense osteoid component attached to the outer cortex over a narrow zone
- imaging features
- large, lobulated, “cauliflower-like” homogeneous mass
- string sign - thin radiolucent sign separating the tumor from the cortex
- tumor stalk - later stage - obliterating the radiolucent plane
- +/- soft tissue mass
- Px and Rx
- usually LOW-GRADE - excellent prognosis!
- surgical resection only
- no need for chemo or radiation

Periosteal osteosarcoma
- a subtype of surface osteosarcoma
- slightly older patient population compared to conventional osteosarcoma
- location
- diaphyseal!
- arises from the cortex; being attached to underlying cortex at orgin
- intramedullary extension rare
- imaging features
- cortical thickening
- scalloping of the cortex
- “wrap around” the circumference of bone
- soft tissue mass
- periosteal reaction common - sunburst or codman triangle
- Px
- intermediate
- better than conventional osteosarc
- worse than parosteal osteosarc

Saying…
“A cannot be ruled out, nor can B”
“A cannot be ruled out, nor can B”
Cervical spine rotation vs subluxation
- cervical spine can rotate with respect to each other if the pt’s neck is rotated
- but subluxation is abnormal –> rotationary instability!!!
When a disc is freshly extruded, how would it look?
- Iso with other discs on T1
- but Hyperintense on T2 for freshly extruded disc
Dolichoectasia
- elongation
- dilatation
If you see slightly hyperdense fluid within the sphenoid sinuses in a trauma patient?
Worry about basal skull fracture
Trauma patient
hyperdense fluid in the mid ear and mastoid air cells
but no acute fracture seen
STILL suspicious for an acute, undisplaced temporal bone fracture!!!
Colpocephaly
A cephalic disorder that refers to the disproportionate enlargement of the occipital horns of the lateral ventricles
is usually diagnosed early after birth due to seizures
Types of pelvic fractures
Young-Burgess Classification
- Lateral compression
- I - ipsilateal sacral #
- II - ipsilateral iliac wing #
- III - contralateral open book #
- AP compression
- I - SI diastasis (8mm- 2cm)
- II - opening of SI jt, disruption of SI,SS,ST ligaments
- III - complete disruption of SI joint
- Vertical shear
*

Pelvic ligaments
- sacroiliac ligament
- sacrospinous ligament
- sacrotuberous ligament
Catamenial pneumothorax
Catamenial pneumothorax is defined as a recurrent pneumothorax occurring within the first 72 h from the onset of menstruation, and is often associated with thoracic endometriosis.
1/3 of all pneumothorax in females referred for surgery
Classification of ovarian tumors
- surface epithelial tumors
- serous
- mucinous
- endometroid
- clear cell
- Brenner
- undifferentiated
- germ cell tumors
- teratoma - mature/immature
- dysgerminoma
- endodermal sinus tumor
- embryonal cell carcinoma
- choriocarcinoma
- sex cord-stromal tumors
- granulosa-stromal cell tumors
- granulosa cell tumor
- fibrothecoma
- sclerosing stromal tumor
- sertoli-stromal tumors
- Sertoli-Leydig cell tumor
- steroid cell tumors
- other tumors
- granulosa-stromal cell tumors
- metastatic tumors
ex·cres·cence
A distinct outgrowth on a human or animal body or on a plant, esp. one that is the result of disease or abnormality.
Osteofibrous Dysplasia
Ossifying Fibroma
- < 20 y/o
- most common location - anterior cortex of the tibia
- painless bony enlargement or as anterior bowing of the affected bone
- complications - pathologic fracture and even pseudoarthrosis formation
- DDx - adamantinoma
- imaging
- anterior tibial cortex
- expansile, eccentric lucency with groundglass matrix and sclerotic margins
- may cause anterior tibial bowing
SMA branches

Saying:
The thin tubular structure favored to represent the appendix in the right lower quadrant demonstrates mild dilation and mural thickening, with associated echogenic fat. This appearance is worrisome for acute appendicitis.
The thin tubular structure favored to represent the appendix in the right lower quadrant demonstrates mild dilation and mural thickening, with associated echogenic fat. This appearance is worrisome for acute appendicitis.
When you see colitis… or diverticulitis… or appendicitis… what do you look for???
Within the resolution of CT, the visualized mesenteric vein, splenic vein, and portal veins are patent with no evidence of mesenteric venous thrombosis.
How do you differentiate
an In-111-octreotide scan
from
an I131-MIBG scan?
- Octreotide - spleen, liver, kidney, bladder and bowel
- MIBG - salivary gland and cardiac uptake
ABC
vs
UBC
ABC
- multiple blood filled cysts
- fluid-fluid levels
UBC
- fallen fragment sign
Gorham’s Disease
- aka Gorham vanishing bone disease, phantom bone disease
- uncontrolled proliferation of distended, thin-walled vascular and lymphatic channels within the bone –> resorption or replacement of bone with angiomas and/or fibrosis
- bone just disappears
ABC
- primary
- AVM or vascular malformation in the bones
- blood filled cystic spaces
- fluid-fluid levels
- secondary
- ABC-like components can be seen in
- GCT
- chondroblastoma
- telangiectatic osteosarcoma
- ABC-like components can be seen in
Ivory vertebral body
Diffuse and homogeneous increase in density of a vertebral body that otherwise retains its size and contours
DDx
- Adults
- osteoblastic metastases
- prostate
- breast
- lymphoma
- paget’s - if posterior elements involvement
- intraosseous hemangioma
- osteoblastic metastases
- Peds
- lymphoma
- osteosarcoma
- osteoblastoma
- metastatic disease
- neurofibroma
- medulloblastoma
- ewing sarcoma
4 stages of carpal dislocation
- Stage I - scapholunate dissociation
- rotatory subluxation of the scaphoid
- disruption of the scapholunate ligament – Terry Thomas Sign
- exacerbated in clenched fist views
- Stage II - perilunate dislocation
- lunate remains aligned with radius
- remainder of the carpal bones dislocated dorsally
- capitolunate joint is disrupted
- 60% associated with scaphoid #
- Stage III - midcarpal dislocation
- triquetrolunate interosseous ligament disruption or triquetral #
- Stage IV - lunate dislocation
- dorsal radiolunate ligament injury
- dislocation of lunate volarly
Mikulicz angle
The angle b/t the femoral neck and femoral shaft
- normal 120-135 degress
- coxa vara < 120
- coxa valga > 135

PVNS
vs
synvovial osteochondromatosis
PVNS does not calcify
Primary vs Secondary
synovial osteochondromatosis
- Primary
- uniform
- Secondary
- secondary to degenerative changes
- varying sizes and shapes
Causes of Madelung deformity
- anything that disturbs the ulnar side of the distal radial growth plate
- vascular insufficiency
- trauma
- infection
- muscular disorders
- associations
- Turners syndrome
- Hurler
- achondroplaia
- Ollier disease
Well corticated but erosive arthritis
When arthritis does not fit a classic pattern
TB arthritis
(Small) particle disease
or
Giant cell granulomatous response
or
Aggressive granulomatosis
- inflammation and osteolysis secondary to shedding of prosthetic components - polyethylene lining and/or methylmethacrylate cement in submicron size
- granulomatous response –> osteolysis
- 1-5 years after surgery
- most often in cemented arthroplasties
- imaging
- lucencies at metal-cement or metal-bone interface should be < 2mm
- if > 2mm, then
- loosening
- infection
- small particle disease
- multifocal lucencies, which may not conform to the shape of prosthesis
- no associated sclerotic rxn
- in the hip - most often in the medial border of tip of femoral component

US
Young woman with RLQ pain
Equivocal Appendix
Inflammatory fat +++ out of keeping with the degree of appendiceal findings
What must you look for???
MUST RULE OUT PID!!!
- If appendix findings are equivocal
- If the RLQ inflamamtory fat is out of keeping with the appendiceal findings
- Look for dilated tubes and other findings to diagnose PID
WHat do you look for in acute colitis/appendicits/diverticulitis?
Mesenteric/splenic/portal venous drainage
r/o venous thrombosis
How do you demonstrate a hiatus hernia on esophagram or upper GI series?
Always remember to roll the patietn to coat barium/water soluble contrast around the esophagus and stomach!
Or else you may miss an HH!!!
(contrast flows right through the esophagus)
Natural indentations on the esophagus?
- aorta
- left mainstem bronchus
- left atrium
- +/- cricopharyngeal muscle
Saying:
By dates, the patient should be … weeks and … days. No intrauterine gestation is seen.
Findings could represent a very early pregnancy but ectopic pregnancy or pregnancy loss cannot be excluded.
No free fluid is identified in the posterior cul-de-sac. An intraperitoneal hematoma is not identified.
Correlation with serum beta HCG and possible repeat ultrasound in 1-2 weeks’ is recommended.
Results were discussed with the patient.
- By dates, the patient should be … weeks and … days. No intrauterine gestation is seen.
- Findings could represent a very early pregnancy but ectopic pregnancy or pregnancy loss cannot be excluded.
- No free fluid is identified in the posterior cul-de-sac. An intraperitoneal hematoma is not identified.
- Correlation with serum beta HCG and possible repeat ultrasound in 1-2 weeks’ is recommended.
- Results were discussed with the patient.
Xanthogranulomatous pyelopnehritis (XGP)

- chronic obstruction (from calculus, stricture, or tumor) –> chronic infection –> suppurative granulomatous rxn
- women > men
- 45-65y/o
- fever, dysuria, flank pain, pyuria
- varies species - proteus, mirabilis, e.coli, staph, klebsiella, pseudomonas, enterobacter, etc
- 3 stages
- 1 - confined to the kidney
- 2 - extension to the peri-renal space
- 3 - extension to the pararenal spaces +/- abdominal wall
- Rx - nephrectomy! Abx is only a temporizing measure
- X-ray - staghorn calculus
- US - enlarged kidney with loss of corticomedullary differentiation; renal parenchyma replaced by hypoechoic masses - often have low level of internal echoes
- CT - best; thinned cortex (long-standing) replaced by low-attenuating masses/cysts; ring enhancing areas of granulomatous tissue; small gas collections may be seen in intra-renal abscesses

Partial agenesis of the pancreas
(Dorsal agenesis - more common)

- pancreas develops from 2 separate ventral and dorsal buds
- both buds have their own duct system
- ventral bud - major papilla + duct of Wirsung
- dorsal bud - main and accessory pancreatic duct (of Santorini)
- S/S - diabetes, nonspecific abdo pain, and idiopathic pancreatitis
Most common variation in pancreatic duct formation is …
…
…
…
Pancreatic Divisum

- 4-10%
- mostly asymptomatic; may have chronic abdo pain or idiopathic pancreatitis
- results from failure of fusion of the dorsal and ventral pancreatic anlages/buds
- dorsal pancreatic duct (accessory duct of Santorini) drains most of the pancreatic glandular parenchyma via the minor papilla
- 3 types
- 1 - classic - no connection at all
- 2 - absent ventral duct - all is drained through the dorsal duct via the minor papilla; major papilla only drains the bile duct
- 3 - filamentous or inadequate connection b/t ventral and dorsal ducts
- vs Annular pancreas
- pancreas completely encircles the 2nd portion of the duodenum; occasionally causing duodenal obstruction

Where does primary breast osteosarcoma
most commonly metastasize to?
To the lungs
via hematogenous spread
Most common subtypes of breast sarcomas?
- fibrosarcomas
- malignant fibrous histiocytoma
- undifferentiated high grade sarcomas
Most common pleural mass lesion?
Malignant mesothelioma
Why do you not give IV contrast to patients with
Sickle Cell Anemia?
Iodinated contrast may lead to acute sickling crisis
Cord astrocytoma
vs
ependymoma
- Astrocytoma - homogeneous well defined, long tumor, expanding the cord
- Ependymoma - more heterogeneous
What does
diffuse annular calcification and fused facet joints
make you think?
Ankylosing spondylitis
Look down to the SI joints!!!
Usually AS starts at the thoracolumbar junction, and extends superiorly and inferiorly
In AS in young women, it may start in ther cervical spine
How does dural AVF happen?
Trauma, or other inciting events –>
dural sinus thrombosis –>
inflammation, and increased vascularization/angiogenesis of the feeding dural arteries (e.g. middle meningeal artery, occipital artery, all from ECA origin) –>
during this process, a potential communication b/t the dural venous sinus and the feeding artery can develop –>
Dural AVF –>
high pressure system; early filling of the involved dural venous sinus compared to the contralateral side –>
in severe cases, pt may have cortical venous reflux!! and may bleed!
Couple
vs
Few
vs
Several
Couple is two.
The order is Couple (2), Few (3-4), Several (5-7).
Choroid plexus cyst
- must be more than 2mm in size
- if >10mm - highly associated with T18
- must document open hands, normal feet, normal heart, etc
- only 12% is associated with other anomalies
- almost all of CPC regress by 32 weeks, so no need to follow up, unless to alleviate anxiety
Serum trip screen results
for T21 vs T18
- beta HCG
- alpha fetal protein
- estriol
- T18
- all 3 are low
- T21
- beta-HCG high
- AFP and estriol are low
Fibroepithelial tumor of the breast
- composed of both stromal and epithelial tissue
- wide range of benign and (rarely) malignant tumors
- fibroadenoma (benign)
- esp if calcifications
- phyllodes (benign or malignant)
- esp if small cystic foci
- fibroadenoma (benign)
- mammo
- US
- MR - moderately rapid and homogeneous intense with or without non-enhancing septations
5 Types of fibromuscular dysplasia

- medial fibroplasia
- 75-80%
- affects tunica media
- beaded appearance
- intimal fibroplasia
- 10%
- collagen deposits around the tunica intima
- concentric, smooth narrowing
- perimedial fibrodysplasia
- <10%
- medial hyperplasia
- 1-2%
- periarterial hyperplasia
- <1%

Typical appearance of liver abscess

- multilobulated
- rim-enhancing
- internal enhancing septations
- peripheral edema
