Random_16 Flashcards
What to do if you see a syrinx the first time?
Give gadolinium contrast
To exclude an underlying mass lesion
Causes for Tc-99m MDP uptake in extraosseous tissues
Tc-99m MDP uptake in extraosseous tissues
- Factors contributing to increased soft tissue uptake
- focal hyperemia
- extracellular fluid expansion
- increased tissue calcium and phosphate concentration
- alterations in the local chemical milieu
- Benign
- site of injection
- soft tissue infection/inflammation - abscess, DVT, radiation-induced soft tissue injury
- prior trauma - heterotopic calcification, myositis ossificans
- tumoral calcinosis
- scarring from surgery
- infarction
- Malignant
- primary malignancy in adults - calcified and mucin-producing tumors, breast and lung cancer
- primary malignancy in children - neuroblastoma (hot on bone scan 70% of the time, also MIBG hot)
- metastatic disease
Ameloblastoma
Ameloblastoma
- benign, locally aggressive tumor
- most common location - mandible
- less common - maxilla
- second most common odontogenic tumor
- odontoma most common
- present at 20-30 y/o
- clinical - hard painless mass near the angle of the mandible in the region of 3rd molar tooth
- 20% associated with dentigerous cysts and unerrupted teeth
- xray/CT
- multiloculated
- expansile “soap bubble” like
- well-demarcated borders
- no matrix calcification
- erosion of the adjacent tooth roots - highly specific
- may erode through the cortex into the adjacent soft tissues
- MRI
- mixed solid/cystic components
- thick irregular walls
- papillary solid structures projecting into the lesion
- enhance +++
- Rx - surgical en bloc resection
- DDx
- dentigerous cyst - the relationship between ameloblastomas and dentrigerous cysts is a controversial one: 20% of ameloblastomas thought to arise from pre-existing dentigerous cysts
- odontogenic keratocyst (OKC) - usually unilocular with thin poorly enhancing walls
- odontogenic myxoma - can be almost indistiguishable
- aneurysmal bone cyst (ABC)
- fibrous dysplasia
Burkitt Lymphoma
Burkitt Lymphoma
- endemic variant
- Africa
- EBV associated
- jaw or other facial bones
- sporadic variant
- outside of Africa
- rarely associated w/ EBV
- ileo-cecal most common location
- immunodeficiency-associated
- HIV
- transplant pts
Post thoracic aortic surgery findings
- Left ventricle apical venting is sometimes used to maintain a dry surgical field during valvular surgery, as was done in this case during ascending aortic aneurysm repair.
- A pledgeted suture is a suture that is supported by a small piece of cloth, commonly used in cardiothoracic surgery.
- The pledget may mimic a pseudoaneurysm or contrast leak. Precontrast images may be useful to differentiate these entities.
Sprain refers to injury of ligaments.
Strain refers to injury of muscles and tendons.
Sprain refers to injury of ligaments.
Strain refers to injury of muscles and tendons.
Most common cause of acute pancreatitis in pediatric population in US?
Most common cause of chronic pancreatitis in pediatric population OUTSIDE US?
Most common cause of acute pancreatitis in pediatric population in US?
- Trauma
Most common cause of chronic pancreatitis in pediatric population OUTSIDE US?
- Tropical pancreatitis
- Tropical pancreatitis is thought to be caused by a combination of malnutrition and ingestion of environmental toxins found, for example, in the cassava plant.
Infantile hemangioendothelioma
- may develop consumptive coagulopathy - Kasabach-Merritt sequence
- natural history of haemangioendotheliomas in infancy is a rapid, proliferative growth phase in the first 6 months of life, followed by regression and involution.
Normal predental space in children vs adults
- Children < 5mm
- Adults < 3mm
Why does pyloric stenosis usually present?
2nd month of life
4-8 weeks old
3mm thick
15 mm long
Debris
There is no plural, and the word is always pronounced without the /s/. It is an uncountable noun:
e.g. There is not much debris remaining from the 9/11 attack.
Debris
There is no plural, and the word is always pronounced without the /s/.
It is an uncountable noun:
e.g. There is not much debris remaining from the 9/11 attack.
Differences in pediatric kidneys vs adult kidneys
on ultrasound?
Pediatric kidneys:
- prominent hypoechoic pyramids
- renal cortex may be echogenic (in neonates)
- no renal sinus fat
Benign enlargment of subarachnoid space in infancy
BESS of infancy
Benign enlargement of subarachnoid space in infancy (BESS)
- male predominant
- majority associated with familial macrocephaly
- transient accumulation of CSF in the frontal region
- thought to be due to delayed development or delayed function of arachnoid villi at the sagittal sinus
- US
- widening of bifrontal and anterior interhemispheric CSF spaces (>5mm)
- no flattening of adjacent gyri
- normal posterior sulci
- normal ventricular size
- key feature differentiating subarachnoid and subdural spaces - cortical veins traversing the subarachnoid spaces
- spontaneous resolution by 2 y/o
Dilated duct due to intraductal papilloma
- Solitary papillomas are usually located centrally in a major duct in the subareolar breast, often within 1 cm of the nipple.
- Multiple papillomas, in contrast, are usually located in the periphery of the breast and are associated with a higher risk of subsequent breast cancer compared to central papillomas.
- Intraductal papillomas are part of a spectrum of papillary lesions, which also includes atypical papillomas and intraductal papillary carcinoma.
- Histologic categorization of papillary lesions can be difficult due to their heterogeneity, and distinguishing a malignant from a benign papillary lesion may be challenging for the pathologist, particularly if only a portion of the lesion is available for review.
- Some studies have shown a significant upgrade rate with surgical excision, while others suggest imaging followup
What to look for in a neonate with an arterial infarct
- Cardiac causes
- Hemoglobinopathy, such as sickle cell dz
In a supine baby, if he/she aspirates, where does it go?
RUL!!!
NG vs NJ tubes?
NG tubes often cause reflux and aspiration, esp in babies
To prevent aspiration, use NJ tube!!!
Cortical pseudolaminar necrosis
Cortical pseudolaminar necrosis, also known as cortical laminar necrosis and simply laminar necrosis, is the (uncontrolled) death of cells in the (cerebral) cortex of the brain in a band-like pattern with a relative preservation of cells immediately adjacent to the meninges.
It is seen in the context of cerebral hypoxic-ischemic insults, i.e. strokes.
Hyperintense on both T1 and T2!!!
What is the normal carinal angle?
70 degrees +/- 10 degrees in adults
if splayed
- subcarinal mass
- LA enlargement
Seen as a small soft-tissue density adjacent to the lateral border of the aortic knob on a frontal radiograph in up to 10% of normal patients
Normally the left superior intercostal vein drains the left 2nd, 3rd, and 4th posterior intercostal veins and connects the left brachiocephalic vein and the accessory hemiazygous vein
As such, the left superior intercostal vein provides a collateral path of blood back to the heart
The size of the left superior intercostal vein is inversely related to the size of the accessory hemiazygous vein: the smaller (or absent) the accessory hemiazygous, the larger will be the left superior intercostal vein
The accessory hemiazygous vein (orange arrow below) drains the posterior intercostal veins from 3-4 intercostal spaces between the left superior intercostal vein (green arrow below) and the uppermost branch of the hemiazygous vein (blue arrow below)
Glabella
the smooth part of the forehead above and between the eyebrows.
Most common lung findings of Wegener’s granulomatosis in children?
Most common airway findings in Wegener’s granulomatosis in children?
Most common lung findings of Wegener’s granulomatosis in children?
- nodules
Most common airway findings in Wegener’s granulomatosis in children?
- stenosis (often subglottic)
Paraneoplastic syndrome associated with
mature cystic teratomas?
Paraneoplastic syndrome associated with mature cystic teratomas?
- Limbic encephalitis
- Cushing syndrome
Grading for chondromalacia
•grade I
focal areas of hyperintensity with normal contour
◦arthroscopically : softening or swelling of cartilage
•grade II
blister-like swelling/ fraying of articular cartilage extending to surface
◦arthroscopically : fragmentation and fissuring within soft areas of articular cartilage
•grade III
◦partial thickness cartilage loss with focal ulceration
◦arthroscopically : partial thickness cartilage loss with fibrillation (crab-meat appearance)
•grade IV
◦full thickness cartilage loss with underlying bone reactive changes
◦arthroscopically : cartilage destruction with exposed subchondral bone
What malignancy is most commonly associated with leptomeningeal carcinomatosis?
What malignancy is most commonly associated with leptomeningeal carcinomatosis?
- breast
- lung
- lymphoma
- leukemia
- melanoma
How to measure for Chiari I malformation
- anterior - basion
- posterior - opisthion
- need to measure from cortical bone to cortical bone (not just the fatty marrow part)
In children, it is common to have prominent perivascular spaces
In children, it is common to have prominent perivascular spaces
Triad of prune belly syndrome
- underdevelopment of anterior abdo wall muscle
- ureteric distention
- bilateral cryptorchidism
Fetal and neonatal tumors are most often supratentorial in location, in comparison to tumors in older children, which are often infratentorial.
Fetal and neonatal tumors are most often supratentorial in location, in comparison to tumors in older children, which are often infratentorial.
3 most prominent features of craniopharyngioma
- mixed solid and cystic
- calcification (>90%)
- enhancement (>90%)
peds craniopharyngioma - often solid/cystic
adult craniopharyngioma - often purely solid
DDx for pituitary stalk lesions
- neoplastic
- germinoma
- hypothalamic glioma
- CNS lymphoma
- pituicytoma
- granular cell tumor
- metastasis
- infectious
- CNS TB
- sequelae of meningitis
- infiltrative
- LCH
- sarcoidosis
- lymphocytic hypophysitis
DDx for pineal tumor in kids
- pineoblastoma
- germ cell tumor
- retinoblastoma (also ocular inovlvement)
- astrocytoma - but more precisely arises from the tectal plate/midbrain
Pineoblastoma
- highly malignant (WHO IV)
- PNET
- highly cellular
- 30% have CSF dissemination
- most present w/ hydrocephalus
- many have localized invasion
- average age of Dx - 3 y/o
Germinoma
- supersellar - 20%
- pineal - 80%
- M:F = 10/1
- in the supersellar region - “hugs” the ventricles
- very chemo/rad sensitive, good 5 year survival
Brainstem glioma
- astrocytoma
- low grade usually
- low attenuation on CT
- “engulfs” the basilar artery
Arc of Buhler
Arc of Buhler
- persistent embryonic connection b/t the celiac artery and SMA
- independent of other collateral pathways b/t celiac and SMA
- GDA
- dorsal pancreatic artery
- travels vertically
- ventral to abdominal aorta
- 1-4% of individuals
Arc of Riolan
Aarc of Riolan
- aka “meandering mesenteric artery”
- meander: to follow a winding and turning course
- connects proximal SMA (or one of its primary branches) to the proximal IMA
- important artery for either proximal SMA or IMA occlusion
- in distal abdominal arotic occlusion, it provides collateral flow from SMA to IMA to iliac vessels (via superior rectal artery) and to lower (via external iliac artery)
Marginal artery of Drummond
Marginal artery of Drummond
- anastomosis of the terminal branches of ileocolic, right colic, and middle colic arteries of the SMA, and of the left colic and sigmoid branches of the IMA, to form a continuous arterial circle and arcade along the inner border of the colon
- important connection b/t SMA and IMA
- junction of SMA and IMA territories is splenic flexure