Random_3 Flashcards
How to confirm intrapancreatic ectopic splenic tissue?
Denatured RBC scan
Malignant degeneration of dermoid cyst
2%
SCC most common
How to differentiate
pulmonary hypertension
from
shunt vascularity
- pulmonary arterial hypertension - vascularity does not go beyond 2/3 into the periphery; pruning
- shunt - shunt vascularity; no pruning
Most common septal defect in Down Syndrome?
AVSD
endocardial cushion defect
goose neck appearance
Types of dural AVF
- Arterial supply from ICA - pial supply
- Arterial supply from ECA, e.g., - occipital artery
- drains directly into the dural venous sinus
What to suspect in a young patient presenting with acute intracranial hemorrhage (ICH)?
AVM
Orbital trauma with wooden foreign body
- For orbital trauma, CT is the first-line modality for imaging evaluation, and it can be helpful to evaluate for the presence of intra-orbital foreign bodies.
- A wood foreign body can be difficult to differentiate from subcutaneous gas and fracture fragments.
- The appearance of wood on CT depends on its hydration;
- Dry pine (dead or cut) is less dense - can look like air density
- While fresh pine is more dense, depending on the degree of air and water content
- Dry wood can be distinguished from air by a reticulated matrix.
DDx for unilateral sacroilitis
- Infection/septic joint***
- OA
- gout
- psoriasis
Synovial sarcoma
- 4th most common sarcoma
- young patients
- close to the knee
- T2 - triple sign - low/intermediate/high signal intensity
- “bunch of grapes” sign
- fluid-fluid level due to internal hemorrhage
Well-corticated juxta-articular erosions
- PVNS
- synovial osteochondromatosis
- gout
- amyloid (also low signal intensity on MR, but not as low as PVNS)
Lesser trochanter avulsion fracture
- always pathologic fracture
- unless HIGH speed MVC
Natural plain film stages of AVN
- sclerosis (relative to normal bone density, whch would be decreased to due to bone resportion secondary hyperemia)
- subchodnral lucency
- collapse
- fragmentation
- end-stage degenerative changes
Important places to look for acute fractures in a foot x-ray
- calcaneus
- anterior process
- posterior tuberosity
- talus
- lateral process
- metatarsals
- base of the 5th MT
Branches of the RCA
- Conus branch
- SA node branch
- Acute marginal branch(s)
- PDA
- posteral lateral branch
What % is considered significant stenosis in coronary arteries?
- Left main > 50% is significant
- Reminder > 75%
senescent changes
senescent changes
Bennett fracture
vs
Rolando fracture
- Bennett - intraarticular fracture of the 1st MC (thumb)
- always associated with subluxation/dislocation of the 1st MC relative to carpal bones
- Rolando - comminuted Bennett fracture
Carcinoid tumors
Can cause intussusception
Upstream bowel will be abnormal-looking due to the intussusception
Achalasia
Mechanium and Causes
- Achalasia - esophageal motility disorder (dismotility)
- absent primary peristalsis
- incomplete relaxation of the LES
- Causes
- Primary - idiopathic - most common*
- loss of normal ganglion cells in the esophageal myenteric plexuses
- Secondary
- malignant tumor at the GE junction
- Chagas’ disease
- Primary - idiopathic - most common*
Median arcuate ligament syndrome
- Diaphgramatic cura compressing the celiac axis
- Breathing in - Okay
- Breathing out - Crux angulation compresses
AS with transverse fracture through the ankylosed spine
Can act like “pseudoarthrosis”
Most common manifestation of rheumatoid arthritis in the chest
Pleural effusions
Complete occlusion of the distal aorta
and proximal iliac arteries
Leriche syndrome
- triad
- absent femoral pulse
- claudication
- impotence
- atrophy/trophic changes
- collaterals
- sup-inf epigastric arteries
- iliolumbar arteries
- paraspinal arteries
Lemierre’s disease
Fusobacterium necrophorum
Sinus venosus ASD
Male breast cancer
1%
of all breast cancer diagnosis
Male breast abscess
Abscess in the male breast is a relatively rare finding, so a more worrisome diagnosis, such as malignancy, must always be excluded.
Achilles tendon rupture
- Achilles tendon is the most commonly injured tendon of the ankle.
- Tears most commonly occur approximately 2-6 cm proximal to the calcaneal insertion – avascular / watershed zone of the tendon.
- Plain film findings are non-specific because the Achilles tendon is not visualized directly by radiography. However, it is outlined anteriorly by the Kager’s fat pad. Findings may include extensive posterior soft tissue swelling and posterior concavity of the Kager’s fat pad.
- MRI is diagnostic and shows high signal with disruption of the normal tendon. Tears more prominent on fluid sensitive sequences and range in spectrum from:
- Interstitial tears – high signal parallel to long axis of tendon. However, the surrounding tendon fibers are intact.
- Partial tears – Heterogenous high signal and tendon thickening without complete disruption
- Complete tears – Complete disruption where tendon fibers may overlap or be distracted. Will have fluid between torn fibers (as in our case)
- Ultrasound can also distinguish complete from partial tears with a 92% accuracy
Lymphoma
- Central hypodense areas likely represent necrosis
- Unusual to have calcifications unless in the case of treated lymphoma
Most common cause of a pancreatic mass lesion in pediatric population?
Lymphoma
Bone lesions that are always on the DDx
- Infection - osteomyelitis
- Mets/myeloma - if >40 yo
- EG - if younger pts
- Osseous lymphoma
3 most common tumors in pediatric population
- leukemia
- brain tumors
- lymphoma
Rx in HL vs NHL
Radiation therapy plays a little role in the routine management of pediatric NHL as opposed to HL.
Mediastinal radiation is not commonly used for patients with mediastinal masses from NHL except in the emergent treatment of symptomatic superior vena cava obstruction or airway obstruction. Even in these cases, low-dose radiation is usually used.
Causes of infiltrative/restrictive cardiomyopathy
- amyloidosis
- sarcoidosis
- hemochromatosis
- glycogen stoarge disease
Perineural spread of tumor
- Although perineural tumor spread most commonly involves the trigeminal and facial nerves, it can affect any nerve, including less well-known connections between the trigeminal and facial nerves (like the auriculotemporal nerve).
- Connection b/t CNV and CNVII - auriculotemporal nerve
- Imaging findings
- thickening of nerve
- abnormal enhancement of nerve
- obliteration of perineural fat pads
- neuroforaminal widening/destruction
- Tumors tend to spread perineurally
- adenoid cystic carcinoma
- squamous cell carcinoma of skin
- Involvement of auriculotemporal nerve - causes TMJ dysfunction
- Auriculotemporal nerve
- best seen on axial images
- coronal images allow for visualization of tumor extension along V3 –> foramen ovale –> Meckel cave
Adenoid cystic carcinoma of the parotid gland
- large, heterogeneously enhancing mass
- low attenuation areas - central necrosis
- extension into the parapharyngeal space
- obliteration of the normal fat pad medial to the right mandibular ramus - tumor infiltration
Adenoid cystic carcinoma of the right parotid gland
- T1 - large, hypointense mass extends posterior to the right mandibular ramus (*) into the right parapharyngeal space
- T1 Post Gad FS - enhancement of the right lateral pterygoid muscle - direct tumor invasion or acute/subacute muscular denervation
*
Perineural spread of adenoic cystic carcinoma
- T2 coronal
- markedly widened foramen ovale (yellow arrow)
- obliteration of normal CSF intensity within the right Meckel cave (green arrow), compared to normal CSF intensity within the left Meckel cave (white arrow)
- perineural spread along V3
- Anatomical sketch
- aruciulotemporal nerve is formed by 2 roots arising from V3 below the skull base
- auriculotemporal nerve course around the middle meningeal artery
- auriculotemporal nerve extends parallel to the posterior ramus of the mandible, to join facial nerve within the substance of the parotid gland
- auriculotemporal nerve is usually not visualized - when clearly seen, concerning for perineural tumor spread
Stages of blood product
- Intracellular oxyHb - hyperacute
- IB
- Intracellular deoxyHb - acute
- ID
- 1-2 days
- Intracellular metHb - early subacute
- BD
- 2-7 days
- Extracellular metHb - late subacute
- BB
- 7-14 days days
- Extracellular hemosiderin - chronic
- DD
- > 14-28 days
Upper lobe predominant lung disease
ST CASH
- S - sarcoidosis
- T - TB
- C - CF
- A - AS - ankylosing spondylosis
- S - silicosis
- H - hystiocytosis X - Langerhans
Hematometrocolpos
- metro- uterus
- colpos- vagina*
- when hematometrocolpos is encountered - important to rule out associated uterine duplication and renal anomalies
- causes of hematometrocolpos
- imperforate hymen
- transverse vaginal septum
- vaginal stenosis
- vaginal atresia
- Herlyn-Werner-Wunderlich syndrome
- uterine didelphys
- obstructed hemivagina
- ipsilateral uterine anomaly
Regional sympathetic dystrophy / RSD
- causes: preceding trauma, surgery, stroke
- bone scan findings
- hot on all 3 phases
- diffuse periarticular uptake on delayed images
- if you see diffuse soft tissue uptake in one limb but no focal bone uptake, what’s the Dx
- lymphedema
What to look for in case of spinal cord edema?
Spinal dural AVF
Venous congestion from AVF
DDx for intramedullary tumor in the spinal cord
- astrocytoma
- enhancing, infiltrating
- ependymoma
- mass-like
- hemangioblastoma
- enhancing
- cavernoma
- just like brain cavernoma - popcorn, hemosiderin rim
- note: cavernoma cannot be seen on angiography
Always look out for cerebral venous infarct!
- often bilateral
- peripheral in origin
- can be due to
- dural venous sinus thrombosis
- cortical vein thrombosis
Dural AVF
vs
Brain AVM
- Dural AVF
- arterial supply from ECA
- reflux into a cortical vein
- venous congestion
- cerebral hemorrhage and edema
- Brain AVM
- arterial supply from pial arteries/ICA
- tangle of blood vessel
- can have feeding artery aneurysm or intra-nidal aneurysm - prone to hemorrhage
Cavernous sinus pathology that leads to propotosis
- acute cavernous sinus thrombosis
- carotid cavernous fistula
- tumor within the cavernous sinus
- however, usually leads to CN compression rather than propotosis
- most often CN6 - most medial!!!
Causes of carotid cavernous fistula / CCF
- ICA-cavernous portion aneurym rupture
- trauma
Classification of CCF
- direct - a hole in the ICA
- indirect - dural fistula - ECA supplies and drains into the cavernous sinus
Alternative drainage pathways for cavernous sinus
- superior ophthalmic vein
- inferior petrosal sinus
Superficial siderosis of the brain
- due to chronic microbleeds in the CSF space
- over the cerebral convexity
- causes
- repetitive trauma
- sarcoid
- amyloid
- chronic meningitis
- if you see siderosis down in the basal cisterns
- always look for a spinal cord ependymoma
- microbleeds migrated superiorly!
Good saying:
My primary diagnostic consideration would include… especially given the clinical setting and index of suspicion. In other special circumstances, … also need to be considered.
How to formulate DDx based on CXR findings and to buy your time
- acute vs chronic
- immune status
Copper beaten skull
a. Prominent convolutional markings – gyral markings on inner table
b. Raised ICP in kids
c. Can be confiened to posterior skull
d. DDx
i. Craniosynostosis
ii. Obstructive hydrocephalus
iii. Intracranial mass lesion
Osteopenia circumscriptae
a. Well-circumscribed lucency in the skull
b. In Paget’s disease
DDx for bronchiectasis
- PCB-L
- Post-infectious
- bacteria
- TB
- non TB MB - MAI
- ABPA
- Congenital
- CF
- Kartegener’s
- William-Campbell
- Mounier-Kuhn
- Bonchial obstruction
- malignancy
- FB
- chronic aspiration
- Loss of lung volume
- traction bronchiectasis
Rx for acute contrast reaction
- Minor reaction
- Benadryl - 50mg IV/IM/PO
- Facial edema/urtiaria
- Epi 1:1000 0.3mg IM (epi pen)
- benadryl
- steroid
- Hypotension
- Epi 1:10000 1cc IV (1amp of epi)
- Hypotension with bradycardia
- Atropine 0.5-1mg
- Pheochromocytoma
- Phentolamine 5mg
- Anaphylaxis
- Solucortef 1g IV or
- Solumedrol 100mg IV
- Seizure
- Ativan 1-2 mg IV/PR
Premedication regime for contrast reaction
- Prednisone
- 50 mg PO 24/12/1 hour before exam
- Benadryl
- 50 mg PO 1 hour before exam
Aortic coarctation
- more common in male > female
- associated with Turner’s syndrome
- associations
- bicuspid aortic valve
- ASD
- VSD
- berry aneurysm
- aortopathy
- types
- preductal
- ductal
- postductal
Aortic valve area
- normal > 2.5cm
- severe aortic stenosis < 0.7cm
What is considered significant coarctation?
- luminal narrowing > 60%
- pressure gradient > 20mm Hg
SSFP
- rapid arise in gradient
- minimize artifact from residual magnitization
- time of flight effect - blood is white
- T2/T1 ratio-weighted
Sarcoidosis likes to affect which cardiac system?
Conduction system
Left sided SVC
- 90% drains into the coronary sinus
- 10% drains into the left atrium
- if left SVC drains into LA
- “unroofing” of the coronary sinus
- SVC –> LA –> CS
- right to left shunt
DDx for vessel anterior to the left main pulm artery
- PAPVR draining into the left vertical vein
- Left sided SVC draining into the SVC
Incidence of bicuspid aortic vavle
- male - 2%
- female - 0.7%
Solitary mass in the liver, what to look for?
Solitary mass in the liver, what to look for?
Whether there is background cirrhosis
Solitary liver mass in a background of cirrhosis
HCC until proven otherwise
Primary hemochromatosis
vs
Secondary hemosiderosis
- Primary hemochromatosis = Pancreas
- Secondary hemosiderosis = Spleen
Hepatic complications of hemochromatosis
- cirrhosis
- HCC
- peribiliary cyst
VHL
- bilateral pheochromocytoma
- epididymal cystadenoma
Sclerosing peritonitis
- Abdominal Cocoon
- Sclerosing encapsulating peritonitis
- encasement of variable lengths of bowel by a dense fibrocollagenous membrane giving the appearance of a cocoon
What to think about when encountering a disease entity?
CAC
- cause
- association
- complication
Posterior fossa cystic lesion with enhancing mural nodule
DDx?
- Peds: juvenile pilocytic astrocytoma (JPA)
- Adults: hemangioblastoma
How to differentiate JPA from hemangioblastoma?
- JPA
- enhancing mural nodule
- the cyst wall often enhances as well*
- Hemangioblastoma
- enhancing mural nodule
- secrets fluid - leads to “pseudocapsule”
- the cyst wall never enhance!*
- may see flow voids in the mural nodule
Ganglioglioma
- favored location = temporal lobe
- children and young adults
- most common presentation - temporal lobe seizures
- pathology
- ganglion cells - mature neuronal elements
- glial - neuroepithelial glial elements
- CT
- iso to hypodense
- often calcified
- enhances in 50% tumor
- MR
- T1 - iso to hypo
- T2 - hyperintense solid components, variable cystic components
- Post-Gad - variable
Scirrhous breast cancer
mets to the orbits - enophthalmos
“Scirrhous”
Term to describe “imploding” sinus from chronic sinuisitis
- atelectatic sinus
- “silent sinus syndrome’
What is lamina papyracea
Medial wall of the ORBITS!!!
When worried about renal collecting system injury
Do delayed scan
Delay for 8-10 minutes then scan
Renal trauma grading per the American Association for the Surgery of Trauma (AAST)
Grade I - contusion or non-enlarging subcapsular hematoma; no laceration
Grade II - superficial laceratoin < 1cm; no collecting system involvement; no expanding perirenal hematoma
Grade III - laceration > 1cm; no extension to the renal pelvis or collecting system; no urine extravasation
Grade IV - laceration extends to renal pelvis or urinary extravasation
Grade V - shattered kidney; devasculariation of kidney due to hilar injury
Emphysematous cystitis
- elderly, diabetic women
- e.coli
- gas in the bladder wall
- gas in the bladder lumen is less specific, can be due to trauma, instrumentation, or bladder fistula (from diverticulitis)
- Rx for emphysematous cystitis - IV Abx
- Rx for emphysematous pyelonephritis - percutaneous drainage or nephrectomy
Causes of cavitating lung lesions
- Infection
- primary - staph, klebsiella, TB, nocardis, fungal, fusobacterium (Lemiere sydnrome)
- secondary - septic emboli
- Inflammation
- rheumatoid nodules
- wegener’s granulomatosis
- Neoplastic
- primary - SCC
- secondary - sarcomatous mets
- Vascular
- PE
Most common cardiac valve to be involved in
infectious endocarditis and septic emboli?
Tricuspid valve
Radiographic features of achondroplasia
- disproportionally large calvarium compared to face
- frontal bossing
- short skull base
- narrowed foramen magnum
- short proximal upper and lower limbs
- anterior flattening of vertebral bodies - bullet shaped
- decreasing interpedicular space as going down the lumbar spine
- ping pong paddle iliac wings
- champagne shaped pelvic inlet
Complications of achondroplasia
- cervicomedullary stenosis*
- hearing impairment
- motor deficits
- sleep disordered breathing
Lesions in the putamen/caudate
vs
Lesions in the globus pallidus
- Hypoxic-ischemic insult - more likely to damage the caudate and putamen; globus pallidus is spared
- Most common cause of bilateral globus pallidus injury - CO poisoning
- DDx
- MDMA
- cocaine
- opiates
- cyanide
How does intraaortic balloon pump work?
- collapses during systole –> reducing afterload –> decrease oxygen demand
- inflates during diastole –> increasing flow towards coronary arteries –> increase oxygen supply
CO poisoning
vs
Methanol poisoning
- CO poisoning - globus pallidus
- DDx: cocaine, opiates, cyanide, MDMA
- Methanol poisoning - putamen
How to measure neck lymph nodes?
- On axial plane!!!
- Long axis!!!
DDx for enhancing intramedullary lesion in the spinal cord
- neoplasm - primary or secondary
- multiple sclerosis
- neuromyelitis optica / Devic disease
- idiopathic transverse myelitis
Spinal cord multiple sclerosis
- multifocal, well-defined
- extend over < 2 vertebral bodies in length
- enhancement of plaques –> active disease
- associated brain lesions
Neuromyelitis optica
- central lesion
- patchy enhancement
- involves > 3 vertebral body length
- associated with unilateral or bilateral optic neuritis; brain involvement is typically absent
Idiopathic transverse myelitis
- lesion occupies > 50% of cross-sectional area
- > 3-4 vertebral body segments
- peripheral enhancement
Intramedullary neoplasms of the spinal cord
- ependymoma
- astrocytoma
- hemangioblastoma
- lymphoma
- metastatic disease
Spinal cord ependymoma
- most often occur in the cervical region
- compressive > infiltrative
- polar cysts*
- blood products - hyperintense on T1
- cap sign - rim of extreme hypointensity at the poles of the tumor secondary to chronic hemorrhage
Spinal cord astrocytoma
- eccentric in location
- poorly defined margins
- polar and intratumoral cysts
- extend over a long segment - about 7 vertebral segments
Spinal cord hemangioblastoma
- consist of a cystic and a highly vascular solid component
- T2 - high signal intensity; flow voids
*
Spinal cord lymphoma
- typically involves epidural space or the vertebral column - extradural location!
- rare if intramedullary
- T1 hypo
- T2 hyper (in contrast to low T2/T2 hypo signal for intracranial lymphomas!!!)
Spincal cord metastasis
- most striking feature -
- usually solitary*
- demonstrates marked surrounding edema that in in disproportion to the the size of the metastasis
