Random_13 Flashcards
L5/S1 spondylolytic spondylolisthesis with severe bilateral L5/S1 neuroforaminal stenosis and severe bilateral L5 nerve root impingement.
L5/S1 spondylolytic spondylolisthesis with severe bilateral L5/S1 neuroforaminal stenosis and severe bilateral L5 nerve root impingement.
- Choroidal fissue is in continuation with the ambient fissure
- It hugs the hippocampus
- It contains choroid plexus and anterior choroidal artery
- It connects to the temporal horn anteriorly and superiorly
- Choroidal fissue is in continuation with the ambient fissure
- It hugs the hippocampus
- It contains choroid plexus and anterior choroidal artery
- It connects to the temporal horn anteriorly and superiorly
Osseous excrecence
Osseous excrecence
PCP pneumonia
- CXR - usually normal; may see subtle groundglass opacities
- HRCT
- Diffuse, symmetric ground-glass opacities are the dominant finding. There may be sparing of the subpleural lung in ~40% of the cases.
- Thin walled cysts in the same distribution as the ground-glass opacities may be seen sometimes. These predispose the patient to pneumothorax.
- Adenopathy and pleural effusions are rare. Consider other diagnoses in this case.
Choroidal fissure and temporal horn of the lateral ventricle are VERY close by, but they don’t communicate.
Choroidal fissure and temporal horn of the lateral ventricle are VERY close by, but they don’t communicate.
Uncal shift
vs
Uncal herniation
- uncal shift - just shifted out
- uncal herniation - bad - on coronal images, the uncus is on the other side of the tentorium! - blown pupil due to compression on the cisternal portion of the CNIII
- death occurs when there is mass effect on the adjacent midbrain
Wernicke’s encephalopathy
- Triad: confusion, ataxia, ophthalmoplegia
- MRI:
- T2 : symmetric increased T2 signal intensity in the
- mamillary bodies
- medial thalami
- tectal plate
- periaqueductal area
- T1 C+ (Gd) : contrast enhancement can also be seen in the same regions, most commonly of the mamillary bodies.
- T2 : symmetric increased T2 signal intensity in the
“Luxury perfusion”
- gyriform enhancement of the cortex following infarct
- usually a few days after the infarct
- due to breakdown of blood-brain barrier
Medulla foot
- Medulla region in India
- also called mycetoma
- fungal (eumycetoma)
- bacterial (actinomycetoma)
- commonly seen in those who walk barefoot, such as agricultural workers
- patients typically present with painless swelling and a draining sinus tracts. The purulent discharge typically contains colored “grains” representing clumps of the causative organism
- Stage 0 – Soft-tissue swelling, which can become nodular and expansive.
Stage I – Extrinsic pressure on the bone causing bone displacement or scalloping. No bone involvement.
Stage II – Periosteal reaction or reactive sclerosis as a result of irritation of the bone surface by the causative organism.
Stage III – Bone erosion or cavitation as a result of penetration of the periosteum and cortex.
Stage IV – Joint involvement with longitudinal spread along a ray of metatarsal bone and phalanx.
Stage V – Horizontal spread limited to two rays of bone and confined to the hindfoot, midfoot, or forefoot.
Stage VI – Uncontrolled infection with multidirectional destruction
Dot-in-circle sign
- This sign refers to the characteristic high intensity spherical lesions on both T1- and T2-weighted images with a tiny central focus of hypointensity, resulting in the “dot in circle.”
- The high intensity spherical lesions are classically surrounded by a network of low intensity material.
- High intensity spherical lesions represent granulomatous inflammation, and the low intensity tissue surrounding the round lesions relate to a fibrous matrix.
- The tiny central focus of hypointensity correlates to the fungus ball or grains.
Cspine CT
Look for prevertebral soft tissue swelling SUPERIORLY!!!
Intact Transverse Ligament C1/2
Torn Transverse Ligament C1/2
Transverse Ligament
- The transverse ligament of the atlas is a thick, strong band, which arches across the ring of the atlas, and retains the odontoid process in contact with the anterior arch.
- In Jefferson’s fracture - C1 fracture
- if transverse ligament is intact - stable - conservative management
- if transverse ligament is disrupted - unstable fracture - surgical management
- Radial tilt is measured on a lateral radiograph.
- The radial tilt represents the angle between a line along the distal radial articular surface and the line perpendicular to the longitudinal axis of the radius at the joint margin.
- The normal volar tilt averages 11degrees (2 - 20 degrees)
FMD
Fibromuscular dysplasia
- Intimal FMD - 5%
- concentric ring-like stenosis
- long segment of tubular stenosis
- Meidal FMD - 90-95%
- medial fibroplasia - 70%
- “beaded”
- medial hyperplasia
- preimedial fibroplasia
- medial fibroplasia - 70%
- Adventitial FMD - <1%
Complications
- renal artery stenosis and hypertension
- renal artery aneurysm - may be complicated by aneurysmal rupture in pregnancy
- dissection and thrombosis
Extracapsular silicone implant rupture
Silicone can be seen in breast tissue or lymph nodes after extracapsular rupture.
Classic ultrasound finding of extracapsular rupture is
- “snowstorm” appearance of echogenic scatter in the tissue adjacent to implant.
- “dirty shadow” posteriorly
Where is Zenker’s diverticulum typically located?
- posteriorly
- above the cricopharyngeus muscle
- at C5-C6 level
DDx for asymmetric breast density
- Inflammatory cancer
- Mastitis
- Trauma
- Invasive cancer (lobular)
CT dose
Rotation time doubled, mA one half
- rotation time S double
- mA half
- mAs same
Increase ptich
causes
Increased noise
Increase ptich
causes
Increased noise
Osteopetrosis
Sandwish vertebrae
Dermatomyositis
Sheet-like calcifications
Maissoneuve fracture
Note the spelling!!!
Maissoneuve fracture
Which surface (articular or bursal) is more commonly involved?
Which surface (articular or bursal) is more commonly involved?
articular surface!!!
- Anterior greater tuberosity cysts associated with tears
- Posterior cysts incidental
- Anterior greater tuberosity cysts associated with tears
- Posterior cysts incidental
DDx for decreased thyroid uptake
- Subacute thyroiditis
- Ectopic thyroid hormone production (eg struma ovarii)
- Factitious thyrotoxicosis
- Previous thyroid surgery
- Congenitally absent thyroid gland
- Expanded iodine pool
- Antithyroid medications
DDx for decreased thyroid uptake
- Subacute thyroiditis
- Ectopic thyroid hormone production (eg struma ovarii)
- Factitious thyrotoxicosis
- Previous thyroid surgery
- Congenitally absent thyroid gland
- Expanded iodine pool
- Antithyroid medications
Tracer for HIDA
- HIDA - Tc Hepato Iminodiacetic Acid (HIDA/Lidofenin) is the old term
- Currently used agents are
- PIPIDA - Tc Paraisopropyl Iminodiacetic Acid
- DISIDA -
Tc Diisopropylacetanilido Iminodiacetic Acid
Dx?
- If child is 2-3 y/o?
- If child is 4-8 y/o?
Meyer dysplasia
Dysplasia epiphysealis capitis femoris
- affects the paediatric hip.
- considered more of a normal hip developmental variation rather than a true dysplasia.
- bilateral in ~ 50% of cases
- 2 - 3 years of age
- male predominance
- usually asymptomatic
- Xray
- the affected epiphysis is smaller in size
- there are often multiple nuclei of ossification, giving the epiphysis a “morulated” appearance
- these then tend to fuse at ~ 5 years of age
- DDx: AVN (Legg-Calve-Perthes disease)
- 4-8 years of age
- AVN
- symptomatic - painful hips
Tidbits
Tidbits
- Perforated and extra-uterine IUD needs to be removed to prevent complications such as bowel perforation
- Ectopic pregnancies are less likely in patients with IUDs compared to patients without IUDs; however, in the setting of pregnancy and a properly positioned IUD, ectopic pregnancies are more likely than intrauterine pregnancies.
Perforated and extra-uterine IUD needs to be removed to prevent complications such as bowel perforation
Ectopic pregnancies are less likely in patients with IUDs compared to patients without IUDs (b/c overall pregnancy rate is lower); however, in the setting of pregnancy and a properly positioned IUD, ectopic pregnancies are more likely than intrauterine pregnancies.
Skull base connections
Anterior to posterior:
- pterygopalatine fossa
- vidian canal
- carotid canal
Cordoma vs Chondrosarcoma
- Cordoma
- enhances progressively
- may have mild restricted diffusion
- Chondrosarcoma
- enhances immediately
- no restricted diffusion
Meningioma vs Schwannoma
- meningioma
- intermediate T2 signal
- schwannoma
- high T2 signal
CN2 - 6 portions
- surrounded by dura - affected by meningioma (not Schwann cells or schwannoma)
- you can never have have meningioma involving the intracranial cn2 / chiasm
CN2 - 6 portions
- surrounded by dura - affected by meningioma (not Schwann cells or schwannoma)
- you can never have have meningioma involving the intracranial cn2 / chiasm
CN 7
- wrap around the nucleus of cn6 - baby bum
- cisternal - IAC - labyrinth - geniculate ganglion (vidian nerve) - horizontal tympanic - mastoid - extratemporal
- cn7 is normal to show enhancement after ganglion segment
- wrap around the nucleus of cn6 - baby bum
- cisternal - IAC - labyrinth - geniculate ganglion (vidian nerve) - horizontal tympanic - mastoid - extratemporal
- cn7 is normal to show enhancement after ganglion segment
CN11
- cervical 1-5
- foramen magnum
- pars vascularis
- SCM and trapezius
CN11
- cervical nerve roots 1-5
- foramen magnum
- pars vascularis
- SCM and trapezius
Tennis elbow
- common extensor tendinitis laterally
- most commonly injuried - extensor carpi radialis brevis
Tennis elbow
- common extensor tendinitis laterally
- most commonly injuried - extensor carpi radialis brevis
Throwing injury
- valgus injury
- ulnar collateral ligament at elbow
- UCL tear - T sign - contrast extravasate out extending ino supra recess and down the arm
- UCL laxity - medial condylitis
- ulnar neuritis
- ulnar stress fracture
- posreromedial impingement - olecranon osteophytes, trochlea chondral injury, loose bodies - tommy John Sx
- valgus injury
- ulnar collateral ligament at elbow
- UCL tear - T sign - contrast extravasate out extending ino supra recess and down the arm
- UCL laxity - medial condylitis
- ulnar neuritis
- ulnar stress fracture
- posreromedial impingement - olecranon osteophytes, trochlear chondral injury, loose bodies
- Tommy John Sx - surgical graft of the UCL
Ulnar nerve
- overuse neuritis
- direct injury - ulnar neuropraxia
- cubital tunnel syndrome
Ulnar nerve
- overuse neuritis
- direct injury - ulnar neuropraxia
- cubital tunnel syndrome
A supra-acetabular fossa
also known as pseudodefect of acetabular cartilage
A supra-acetabular fossa
also known as pseudodefect of acetabular cartilage
- is an antatomic variant whereby a focal defect is evident within the subchondral bone of the acetabular roof
- no associated bone marrow edema, cartilage damage or anything
- It is seen in as many as 10% of hips
- typically located at the 12 o’clock position both in the coronal and sagittal planes.
Weigert-Meyer law
the upper pole moiety ureter drains infero-medial to the normal lower moiety ureter.
Upper obstructs
Lower refluxes
Weigert-Meyer law
the upper pole moiety ureter drains infero-medial to the normal lower moiety ureter.
Upper obstructs
Lower refluxes
Autoimmune pancreatitis
has characteristic hypodense capsule
Autoimmune pancreatitis
has characteristic hypodense capsule
Most common benign salivary gland tumor?
Benign mixed tumor (BMT)
AKA pleomorphic adenoma
- May undergo malignant degeneration - carcinoma ex-pleomorphic
Unilateral cystic renal disease
- unilateral
- non-progressive
- non-heritable
- do not cause hypertension
Unilateral cystic renal disease
- unilateral
- non-progressive
- non-heritable
- do not cause hypertension
Achalasia
- primary - Auerbach plexus
- secondary
- Chagas’ disease
- carcinoma
- scleroderma
- stricture
Achalasia
primary - Auerbach plexus
secondary
Chagas’ disease
carcinoma
scleroderma
stricture
Indications for CABG
- left main dz
- triple vessel dz
- 1 or 2 vessel dz involving proximal LAD
- refractory symptoms
Indications for CABG
- left main dz
- triple vessel dz
- 1 or 2 vessel dz involving proximal LAD
- refractory symptoms
What to think about in patients with fever and CN6 nerve palsy?
Sphenoid sinus?
extending into the cavernou sinus and maybe cavernous sinus thrombosis leading to CN palsy
Differences in T2 signal intensity of central scar in
FNH
vs
Fibrolamellar HCC
- FNH - central scar is T2 HYPERintense
- Fibrolamellar HCC - central scar is T2 HYPOintense
Always look for phleboliths for underlying vascular lesions
Always look for phleboliths for underlying vascular lesions
CMR appearance of Fabry disease
- symmetric myocardial hypertrophy
- LGE in midwall in an inferolateral basal distribution
Amyloidosis on CMR
Subendothelial LGE
Wall-Off Necrosis of the pancreas
It is imperative for the radiologist to recognize the CT findings that suggest a diagnosis of WON versus pancreatic pseudocyst and communicate this to the referring physician. CT findings that favor a diagnosis of WON include a thick-walled intra- or extrapancreatic collection containing heterogenous nonliquid (often fat) attenuation debris, pancreatic deformity, and absence of dilatation of the main pancreatic duct.
Wall-Off Necrosis of the pancreas
It is imperative for the radiologist to recognize the CT findings that suggest a diagnosis of WON versus pancreatic pseudocyst and communicate this to the referring physician.
CT findings that favor a diagnosis of WON include a thick-walled intra- or extrapancreatic collection containing heterogenous nonliquid (often fat) attenuation debris, pancreatic deformity, and absence of dilatation of the main pancreatic duct.
Renal stent is difficutl to see on ultrasound
without hydronephrosis
Renal stent is difficutl to see on ultrasound
without hydronephrosis
Malaria –>
Hemolysis –>
Pigment gallstones
Malaria –>
Hemolysis –>
Pigment gallstones
Rx for vesicoureteric reflux
STING procedure
Endoscopic techniques with subureteric injection of bulking agents, also known as
STING (Subureteral Teflon INjection)
Shape of Cafe-au-lait spots in
McCune Albright syndrome
vs
Neurofribromatosis
- McCune-Albright Syndrome - coast of Maine
- Neurofibromatosis - coast of California
McCune Albright Syndrome
vs
Mazabraud Syndrome
- McCune Albright Syndrome
- cafe-au-lait spot
- polyostotic fibrous dysplasia
- endocrinopathy - precocious puberty
- Mazabraud Syndrome
- polyostotic fibrous dysplasia
- intramuscular myxomas
Fibrous dysplasia
esp. Polyostotic FD in McCune-Albright Syndrome
Fractures of the femoral neck tend to result in a varus deformity known as a “Shepherd Crook.” Leg-length discrepancies are common.
Malignant transformation of fibrous dysplasia is rare and commonly believed to be radiation-induced with osteosarcoma, fibrosarcoma, chondrosarcoma.
Fibrous dysplasia
esp. Polyostotic FD in McCune-Albright Syndrome
Fractures of the femoral neck tend to result in a varus deformity known as a “Shepherd Crook.” Leg-length discrepancies are common.
Malignant transformation of fibrous dysplasia is rare and commonly believed to be radiation-induced with osteosarcoma, fibrosarcoma, chondrosarcoma.
Its very uncommon to have DVT in children
If you see one, ask for history
such as line insertion or coagulopathy
Its very uncommon to have DVT in children
If you see one, ask for history
such as line insertion or coagulopathy
SMA syndrome
- Vascular compression of the third portion of duodenum between the aorta and superior mesenteric artery
- primarily attributed to loss of the intervening mesenteric fat pad (most commonly from weight loss).
- SMA is an unusual cause of proximal gastrointestinal obstruction.
- Imaging findings of SMA syndrome include
- abrupt cutoff of the third portion of the duodenum with proximal dilatation
- aortomesenteric angle of <25° (measured on sagittal plane)
- aortomesenteric distance of <8 mm
- partial relief of obstruction may be demonstrated using fluoroscopy by turning the patient prone.
Median arcuate ligament syndrome
vs
SMA syndrome
vs
Nutcracker sydnrome
- median arcuate ligament syndrome
- compression of celiac artery
- SMA syndrome
- loss of intervening mesenteric fat pad due to weight loss
- compression of 3rd portion of duodenum
- leads to stomach and duodenal obstruction
- aortomesenteric angle < 25
- aortomesenteric distance < 8mm
- nutcracker syndrome
- compression of the left renal vein by the SMA
Development of sinuses
Born with ME
Go to School
Frontal after
- at birth - Maxillary sinus and Ethmoid sinus
- go to school - Sphenoid sinus
- frontal sinuses develop later
Wormian bones
Wormian bones, also known as intra sutural bones,[1] are extra bone pieces that occur within a suture in the cranium. These are irregular isolated bones that appear in addition to the usual centers of ossification of the cranium and, although unusual, are not rare.[2] They occur most frequently in the course of the lambdoid suture, which is more “tortuous” than other sutures. They are also occasionally seen within the sagittal and coronal sutures
PORK CHOP
Pycnodysostosis
Osteogenesis imperfecta
Rickets
“Kinky-hair” Menke’s syndrome
Cleidocranial dysostosis
Hypoparathyroidism and hypophosphatasia
Otopalatodigital syndrome
Primary acro-osteolysis
Down’s syndrome
Types of cholangiocarcinoma
Based on location
Based on growth pattern
- based on location
- peripheral
- hilar*
- extrahepatic
- based on growth pattern
- peripheral mass forming
- periductal infiltrating*
- intraductal polypoid
Liver masses T2 brightness
Cyst > Hemangioma > Malignant lesions
Liver masses T2 brightness
Cyst > Hemangioma > Malignant lesions
Liver cluster sign
Pyogenic abscess
Most common liver abscess etiology worldwide
Entamoeba Histolytica
What type of RCC do VHL patients get?
What type of RCC do Birt Hogg Dube pts get?
VHL –> Clear cell RCC
(as opposed to papillary RCC)
BHD –> chromophobe RCC
(cutaneous folliculomas)
Which enzyme is implicated in paragangliomas?
Succinate dehydrogenase
NF-1
hyperintense white matter lesions
Vacuolization of myelin
increases in the 1st decade
then subsides
NF-2
MISME
NF-2 - MISME
- Multiple inherited Schwannomas
- Meningiomas
- Ependymomas
Lynch syndrome
- colon cancer
- ovarian cancer
- endometrial cancer
Cowden syndrome
- Lhemitte Duclos disease - cerebellum
- thyroid cancer
- breast cancer
Most common cardiac mass?
Most common cardiac tumor?
Most common primary cardiac tumor?
Most common primary cardiac malignancy?
- most common cardiac mass - thrombus
- most common cardiac tumor - metastasis
- most common primary cardiac tumor - myxoma
- most common primary cardiac malignancy - angiosarcoma
PRES
15% can have hemorrhage
15% can enhance
PRES
15% can have hemorrhage
15% can enhance
Flagyl CNS toxicity
Flagyl CNS toxicity
- inferior colliculus
- dentate nucleus
- splenium
Septo-optic dysplasia
- absent septum pellucidum
- optic nerve/chiasm hypoplasia
- pituitary hypoplasia
- truncated infundibulum
- posterior pituitary ectopia
Location of IMA relative to IMV
IMA is lateral to IMV
Coronary artery bypass graft types
- LIMA and RIMA the best
- saphenous vein graft
- intimal hyperplasia
- low long term patency
- radial artery graft
- prone to spasm
Crista terminalis
the division b/t the smooth and rough parts of the RA
What to do with painless lacrimal masses?
Biopsy
Always biopsy painless lacrimal masses
Bilateral painless lacrimal masses
DDx
- sarcoidosis
- lymphoma
- Sjogren’s
Involvement of the Tolosa Hunt Syndrome
- orbital apex
- superior orbital fissure
- cavernous sinus
IgG4 related entities
- orbital inflammation
- pancreatitis
- Reidel thyroiditis
- cholangitis
DDx for large orbits/large eyes
- high myopia
- nearsighted
- long eyes
- weakness in the sclera –> staphyloma (focal bulge)
- elongated
- buphthalmos
- infants
- congenital glaucoma
- large eye/large cornea/large anterior chamber
- uniformly large (round)
DDx for small eyes/anophthalmia/microphthalmia
- colobomatous microphthalmia
- defect along the embryonic fissure
- uvea can collapse out
- decreased intra-ocular pressure –> small eyes
- PHPV
- phthisis bulbi
- shrunken calcified non-seeing eye
Coloboma
vs
Staphyloma
- Coloboma
- defect in the sclera
- congenital
- inferior globe
- associated with small eyes
- Staphyloma
- weakening of the sclera
- focal bulge
- acquired
- posterior globe
- associated with large eyes (myopia)
Things to look for in ocular trauma
- presence of foreign body
- if present - OR within 6 hours
- if absent - OR next day
- evidence of globe rupture
- anterior chamber
- lens
- pre-existing Marfan syndrome
- dislocation
- traumatic cataract
- fluid enters the lens
- decreased density than normal protein
- posterior chamber rupture
Leukocoria
- loss of normal red reflex
- most common cause - retinoblastoma
- other causes
- PHPV
- Coat’s disease
Retinoblastoma
Retinoblastoma
- most common peds intraocular tumor
- calcification
- high nuclear/cytoplasm ratio
- high T1 low T2
- enhancement
- look for the contralateral eye
- look for optic nerve involvement
- intracranial PNET’s in regions:
- pineal
- suprasellar
- parasellar
Persistent Hyperplastic Primary Vitreous
PHPV
PHPV
- 2nd most common cause of leukocoria (behind retinoblastoma)
- persistence of primary vitreous extending along retina to lens in the Cloquet’s canal
- microphthalmia
- hemorrhagic retinal detachment
- retrolental soft tissue
- no calcificatios
Coats disease
- primary retinal telangiectasia
- subretinal lipoproteinaceous effusion
- hyper on T1, hypo T2
Most common intraocular malignancy in adults?
Choroidal melanoma
Dacrocystitis
vs
Dacroadenitis
- Dacrocystitis
- inflammation of the lacrimal duct
- pre-septal
- Dacroadenitis
- inflammation of lacrimal gland itself
- post-septal
Pre-septal cellulitis
vs
Post-septal cellulitis
- different venous drainage
- post septal cellulitis drains into the cavernous sinus –> may lead to cavernous sinus thrombosis!
Most common intra-ocular tumor in children
Most common intra-orbital tumor in children
Most common intra-ocular malignancy in adults
Most comon intraorbital mass in adults
- most common intra-ocular tumor in children - retinoblastoma
- most common intra-orbital tumor in children - rhabdomyosarcoma
- most common intra-ocular malignancy in adults - choroidal melanoma
- most common intra-orbital mass in adults - cavernous malformation/hemangioma
Vascular lesions of the orbit
Vascular lesions of the orbit
- venolymphatic malformation
- hemangioma - infantile vs congenital
- cavernous malformation
Orbital infection spectrum
preseptal cellulitis (due to abrasions/trauma) –>
postseptal cellulitis (due to sinusitis - mostly ethmoid, trauma) –>
subperiosteal abscess –>
orbital cellulitis –>
cavernous sinus thrombosis
- proptosis
- ophthalmoplegia
- enlarged extraocular muscles
- enlarged/thrombosed superior ophthalmic veins
- mycotic aneurysm of the cavernous ICA
