Small bowel

Question 1

layers of the small intestine

Answer 1

serosa, muscularis, submucosa, mucosa

valvulae conniventes create SB fold pattern

Question 2

blood supply of small bowel

Answer 2

SMA supplies jejunum and ileum

Question 3

jejunum vs ileum

Answer 3

jejunum: larger; feature full folds and larger villi compared to ileum

Question 4

sbo causes

Answer 4

adhesions, neoplasm, stricture, intussusception

Question 5

XR findings of SBO

Answer 5

air fluid levels; lack of gas in colon, small bowel distention

false positives: ileus with colectomy, ileus with ascites

Question 6

CT findings of SBO

Answer 6

small bowel distention >3cm with transition point; simple vs closed-loop; ischemia (engorged mesenteric vessels, ascites surrounding bowel, wall thickening, lack of bowel wall enhancement, pnsumatosis intestinalis); small bowel feces sign

Question 7

closed loop obstruction

Answer 7

obstruction of both efferent/afferent segments of bowel

whirl sign or U shaped distribution of bowel loops radially around vessels

Question 8

external hernia

Answer 8

inguinal, obturator, ventral hernia

inguinal hernias are common cause of obstruction

Question 9

inguinal hernias

Answer 9

indirect: males; neck of hernia lateral to inferior epigastric vessels; travel into the scrotum; due to patent processus vaginalis
direct: neck is medial to inferior epigastric vessels; week anterior abdominal wall

Question 10

obturator hernia

Answer 10

bowel herniates through obturator canal; pelvic floor laxity/elderly women

find bowel between pectineus and obturator muscles

Question 11

transmesocolic hernia

Answer 11

seen with roux en y gastric bypass or biliary enteric anastamosis from liver transplant

Question 12

paraduodenal hernia

Answer 12

cluster of bowel betwen pancreas/stomach

previously most common internal hernia prior to gastric bypass

left sided; associated with abnormal rotation of intestine

chronic posprandial pain that relieved by massaging

Question 13

foramen of winslow hernia

Answer 13

communication between lesser sac and greater peritoneal cavity

dilated bowel loops in upper abdomen; mesentery between iVC and main portal vein

Question 14

obstruction due to neoplasm

Answer 14

adenocarcinoma, GIST, carcinoid, melanoma, ovarian, lung cancer

melanom is known to cause intussusception

aneurysmal expansion of SB with lymphoma

Question 15

obstruction due to crohn disease

Answer 15

stricture or active enteritis can cause fibrostenosis

Question 16

obstruction from gallstones

Answer 16

gallstone erodes through small bowel&raquo_space; Rigler’s triad

Question 17

Rigler’s triad

Answer 17

pneumobilia, SBO, ectopic gallstone within small bowel

Question 18

Crohn disease

Answer 18

chronic granulomastous inflammation from mouth to anus

skip lesions; TI involvement

apthous ulcers in submucosa

Question 19

imaging findings of crohns disease

Answer 19

wall thickening of TI

cobblestone appearance from crisscrossing deep ulcerations

Question 20

crohn disease complications

Answer 20

bowel strictures, fistula, abscesses

Question 21

scleroderma

Answer 21

deposition of collagein into organs/skin

impaired motility due to replacement of muscular layers of collagen&raquo_space; slow transit/bacterial overgrowth, dilation, pseudoobstruction

Question 22

hidebound bowel

Answer 22

thin , straight bowel folds stuck together

Question 23

scleroderma findings

Answer 23

sacculations on antimesenteric border and hidebound bowel

Question 24

treatment for scleroderma

Answer 24

abx for bacterial overgrowth; prokinetic drugs like erythromycin/octreotide for bowel motility

Question 25

celiac disease

Answer 25

sprue, gluten sensitive enteropathy; autoimmune proximal enteritis from T-cell mediated immune response triggered by gluten

involves duodenum and jejunum

Question 26

imaging findings of celiac disease

Answer 26

reversal of jejunal and ileal fold patterns;

loss of jejunal folds and compensatory increase in number of ileal folds

flocculations of barium due to lack of contrast adhesion to bowel in jejunum

moulage apperance of featureless jejunum

fluid filled bowel with intraluminal flocculations; mesenteric adenopathy, engorgement of mesenteric vessels

Question 27

complications of celiac disease

Answer 27

small bowel T cell lymphoma, intussusception, pneumatosis intestinalis, splenic atrophy, venous thromboembolism, lab abnormalities, cavitating mesenteric lymph node syndrome (CMLNS)

Question 28

low attenuation mesenteric lymph nodes

Answer 28

cavitating mesenteric lymph node syndrome, TB, whipple, treated lymphoma,

Question 29

T cell lymphoma

Answer 29

exophytic mass, circumferential bowel wall thickening, enlarged mesenteric LN

Question 30

causes of infectious enteritis

Answer 30

yersinia, TB affect TI

salmonella causes segmental distal small bowel thickening

Question 31

radiation enteritis

Answer 31

adhesive/fibrotic changes to mesentery and small bowel

history of radiation therapy and regional involvement of bowel loops not confined to a vascular territory

Question 32

whipple disease

Answer 32

infection by tropheryma whippeli&raquo_space; gi tract malabsortion and abdominal pain, arthralgias, increased skin pigmentation

low attenuating adenopathy

thickening/nodularity of duodenum and proximal SB folds

Question 33

GVHD

Answer 33

bone marrow transplant complication

nonspecific wall thickening and effacement of normal small bowel fold pattern; ribbon bowel on GI study