Core Radiology 10/28/07

Front 1

where are valvulae connectivae found?

Back 1

most in jejunum, less in ileum, non in colon

Front 2

what causes thickened mucosal folds in the small bowel? (>3cm)

Back 2

1) FLUID/EDEMA (ischemia, hypoproteinemia); 2) BLOOD (trauma, anticoag); 3) PUS (infection); 4) LYMPH; 5) CELLS (lymphoma, leukemia); 6) STUFF (amyloid, glycogen)

Front 3

what causes barium dilution on SBFT?

Back 3

increased secretions (eg from cryptsporidium) --> see a point after which barium contrast becomes less prominent?

Front 4

how to differentiate diarrhea and obstruction on abdominal plain film?

Back 4

both have a/f levels, but diarrhea has normal caliber SB, obstruction has dilated loops

Front 5

MCC mechanical SBO (2)

Back 5

adhesions and hernias

Front 6

strictures and skip lesions

Back 6

crohn's disease

Front 7

displacement of loops in which IBD?

Back 7

Crohn's -- transmural inflammation --> inflammation of mesenteric "creeping" fat --> displacement

Front 8

radiologic findings with crohn's

Back 8

STRICTURES with increased surrounding MESENTERIC fat, ulcers, SKIP LESIONS; STRING SIGN, COMB SIGN (increased visualization of mesenteric vessels due to fat hypertrophy), PSEUDODIVERTICULAE

Front 9

common complications of crohn's seen by radiology

Back 9

abscesses, fistuale --> aberrent air, bowel obstruction, extraintestinal (sacroiliitis, stones, ascending cholangitis, pancreatitis)

Front 10

what is "comb sign"

Back 10

seen with crohn's disease: increased visualization of vessels in mesenteric fat due to fat hypertrophy from transmural inflammation

Front 11

what does ahaustral colon suggest?

Back 11

ulcerative colitis; aka leadpipe colon

Front 12

complications of UC

Back 12

toxic megacolon, colonic adenocarcinoma, extrainstestinal (sacroiliitis, stones, ascending cholangitis, pancreatitis)

Front 13

what imaging study contraindicated with toxic megacolon?

Back 13

BE -- mucosa very friable

Front 14

differential for ahaustral colon (5)

Back 14

1) LAXATIVE abuse; 2) UC; 3) ISCHEMIA; 4) chronic CONSTIPATION; 5) s/p RADIATION

Front 15

which two segments of GI should be featureless on double contrast study?

Back 15

esophagus and colon

Front 16

linear / filiform polyposis seen with what dz?

Back 16

"burnt-out" IBD -- regenerative foci

Front 17

what causes pneumocystis coli?

Back 17

may be due to bug, may be due to constipation; can be asymptomatic

Front 18

sequence of findings with untreated ischemia

Back 18

aperistaltic loop (sentinal loop) --> thumbprinting --> pneumatosis coli --> perf or portal venous gas

Front 19

what is thumbprinting?

Back 19

thickened mucosal wall (usu 2/2 ischemia --> scalloped mural indents --> bowel air with sharp angles

Front 20

smooth cecal polyp with fat density on CT scan

Back 20

lipoma

Front 21

"mexican hat sign"

Back 21

polyp on stalk seen on plain film; NOT MALIGNANT (cancers on stalks are BENIGN)

Front 22

what does sigmoid volvulus look like on radiology?

Back 22

"coffee bean sign:" central white line separating lumens

Front 23

hallmark feature of intussception on CT

Back 23

mesenteric fat within lumen of bowel

Front 24

whats the dx? CT with thickened bowel wall with trapped air

Back 24

diverticulitis

Front 25

what does appendicitis look like on CT?

Back 25

ARROW SIGN: pointed luminal contour of barium contrast

Front 26

how to dx inguinal hernia on plain film?

Back 26

look for air / bowel overlying obturator foramen

Front 27

which lobes of liver spared in cirrhosis?

Back 27

caudate and left lobe (relative enlargement)

Front 28

radiographic findings in cirrhosis

Back 28

shrunken nodular liver with relative enlargement of caudate and left lobes, splenomegaly, varices / collateralization

Front 29

what does spleen look like on mri?

Back 29

T1: darker than liver (approx = muscle); T2: brighter than liver

Front 30

what are gamna-gandy bodies?

Back 30

aka siderotic nodules -- nodules of fibrous tissue + ?calcium salts, usu seen on MRI -- areas of low signal intensity on T1

Front 31

what causes gamna-gandy bodies (siderotic nodules)?

Back 31

cirrhosis, AML, sickle cell anemia, hemoglobinopathies

Front 32

which organs affected in polycystic disease

Back 32

kidneys --> liver --> pancreas (NOT SPLEEN)

Front 33

what does spleen look like in sickle cell anemia?

Back 33

small, calcified (autosplenectomy)

Front 34

what does splenic hemangioma look like?

Back 34

centripetal enhancement on CT +/- central scar

Front 35

most common benign tumor of the spleen

Back 35

hemangioma; others benign focal lesions: lymphangioma, cyst, calcification, abscess, infarct

Front 36

mgmt of splenic artery aneurysm

Back 36

close monitoring with US (b/c of rupture risk); consider splenectomy based on size of aneurysm, other factors

Front 37

in a pt with known malignancy, what do multiple homogenous lesions in the spleen suggest?

Back 37

mets

Front 38

causes of malignant focal lesions in the spleen (3)

Back 38

1) METS; 2) LYMPHOMA; 3) LEUKEMIA

Front 39

hemosiderosis vs hemochromatosis

Back 39

HEMOSIDEROSIS: RES only (liver, spleen; no pancreas), no end organ dysfunction; HEMOCHROMATOSIS: iron in the parenchyma (liver, pancreas; no spleen); end organ dysfunction

Front 40

what does hemosiderosis look like on MRI?

Back 40

low signal in liver and spleen on T1

Front 41

what does splenic sarcoid look like?

Back 41

spleen with scalloped nodular border

Front 42

air pockets seen in the spleen with what pathology?

Back 42

abscess

Front 43

indications for splenectomy