Small Bowel Flashcards Preview

Gastrointestinal > Small Bowel > Flashcards

Flashcards in Small Bowel Deck (92):
1

DDx for smooth surfaced filling defect in jejunum

GIST
Hemangioma
Lipoma
Metastasis
Lymphoma

2

Where in the small bowel do lipoma usually occur? What is a key differentiating feature?

Distal in the small bowel
Compressibility!

3

What is the difference between lipoma and liposarcoma?

Lipoma will be homogeneously fat

Liposarcoma will have a soft tissue component

4

What is the DDx for multiple small bowel lesions on SBFT?

Lymphoma, Polyposis, Hemangioma, Neurofibroma, Metastases

5

Where do hemangiomas usually occur?

What syndromes have an increased incidence?

Jejunum

Turner
Tuberous sclerosis
Blue rubber nevus
Rendu-osler-weber

6

What is CT enterography?

IV contrast enhances the bowel wall

Water attenuation luminal contrast enhances the lumen

7

How do hemangiomas present on CT?

CAN have calcifications

Small tufts of enhancement within the bowel wall

8

What two syndromes are associated with diffuse hemangiomatosis

Klipper-trenauny-Weber (varicose veins, cutaneous hemangiomas, soft tissue/bone hypertrophy)

Maffuic (enchondromas, subcutaneous cavernous hemangiomas)

9

Cauliflower like grouped polyps in the jejunum in a

Peutz Jeughers (Hamartomatous polyps)

10

What cells do carcinoid tumors arise from? What do they produce? What size does malignant transformation occur? Where are they found in the small bowel?

What is the radiographic appearance?

Kulchitsky cells (APUD), usually 2-3cm
Serotonin
>1cm
Distal small bowel, within 2 feet of ileocecal valve

Cause a fibrotic reaction leading to kinking of the bowel with obstruction.

11

Starburst appearance with linear stranding radiating from a central mesenteric mass with calcification indicates what?

Metastatic carcinoid to the small bowel

12

How do carcinoid mets to the liver present?

Hypervascular mass with central necrosis

13

Who is at risk of small bowel lymphoma?

AIDS
Celiac disease
Crohns
Lupus

14

Which lymphoma is most common in the small bowel?

NHL

15

What are the 4 classifications of small bowel lymphoma?

Which is most common?

Multiple nodules - most common, can cross IC valve
Infiltrating
Polypoid - can be "pseudopedunculated"
Endo-exoenteric

16

DDx for a focal segment of small bowel with smooth mucosa and loss of folds.

Differentiate them

Ischemia - will have narrowed lumen
Amyloidosis - may cause fold thickening
Lymphoma - wont have associated fibrosis, thus causing dilation (vs narrowing with ischemia)

17

Differentiate small bowel lymphoma vs ischemia

Ischemia will cause lumenal narrowing

18

Differentiate hodgkins vs nonhodgkins in the small bowel

Hodgkins will incite a desmoplastic reaction, causing luminal narrowing

19

What type of lymphoma in AIDS patients?

B-cell lymphoma

20

What helps to differentiate malignant GIST vs lymphomas?

adenopathy

21

Where is primary adenocarcinoma most commonly found in the small bowel? What is a known risk factors?

Proximal, duodenum

Adult celiac disease

22

How do malignant GIST spread?

Hematogenous and peritoneal spread

23

How common is small bowel mets in metastatic melanoma?

50% at autopsy

24

Bulky intraluminal mass in the retroperitoneal duodenum suggests what?

Invasive renal cell carcinoma

25

Large cavitated mass devoid of mucosal markings with destruction of the bowel wall can be seen with what 3 entities?

Lymphoma, malignant GIST, colon cancer mets

26

Where are the 3 most common sites of intraperitoneal seeding? How does it present radiographically?

Pouch of douglas, ileocecal region, superior aspect of sigmoid

Displaced bowel loops with narrowed lumen causing angulation and kinking of loops with fold tethering

27

Where is the most common location of a duplication cyst?

Terminal ileum

28

Biliary gas and mechanical SBO suggests what?

Gallstone ileus

29

Describe the pathphysiloigy of ascariasis infection

Ingested eggs hatch in the small bowel and penetrate the mucosa

Travel up to lungs by lymphatics/portal system

Travel up bronchi and are swallowed and shed infections eggs

30

DDx for thin (

Mechanical obstruction
Paralytic Ileus
Scleroderma
Sprue

31

What are the 5 questions to ask with an SBO?

1 - is there an SBO
2 - where is the obstruction
3 - What is the cause of the obstruction
4 - Are there complications
5 - How should they be treated

32

Most common cause of mechanical SBO?

Adhesions

33

What helps to differentiate paralytic ileus vs obstruction

Gas in the colon distal to obstruction

34

How does scleroderma present in the small bowel?

"hidebound" - dilation and crowding of straight and thin mucosal folds

sacculations of antimesenteric border, occasional pneumotosis cystoides intestinalis (can be due to steroid use)

35

Differentiate sprue from scleroderma

Sprue will have hypersecretion and normal peristaltic activity

36

How does sprue present?

Jejunization of the ileum - adaptive response to loss of absorptive surface in proximal small bowel by villous atrophy

Decrease in number of proximal jejunal folds (

37

DDx for Thick (>3mm) straight folds

Segmental?
Diffuse?

Segmental - ischemia, radiation enteritis, intramural hemorrhage, adjacent inflammation

Diffuse - venous congestion, hypoprotenemia, cirrhosis

38

What are the causes of bowel ischemia? most common?

arterial hypoperfusion (most frequent)
embolization
venous thrombosis

39

What is the pathophysiologic timescale of events in bowel ischemia?

What are the 3 possible outcomes?

Submucosal edema and intramural hemorrhage
transmural ischemia
necrosis

Complete healing
Stricture formation
Perforation

40

Radiographic findings of ischemia?

Isolated, rigid dilated and unchanging small bowel loop with thickened mucosal folds

41

Which portion of GI tract is most susceptible to radiation? At what dose>

Small bowel

>40 Gy

42

What is the pathologic process for radiation? How long before chronic changes?

What are the imaging characteristics?

Endarteritis obliterans. >6 weeks

Fold thickening and serration, nodularity and thumbprinting later on

43

Stack of coins appearance of the small bowel suggests what?

Intramural hemorrhage.

44

What associated findings suggest hypoproteinemia as a cause of diffuse fold thickening

Ascites, anasarca

45

DDx for segmental, thick (>3mm) nodular folds

Crohns
Infection
Lymphoma
Metastases

46

DDx for diffuse, thick (>3mm) nodular folds

Whipple disease
Intestinal Lymphangiectasia
Nodular lymphoid hyperplasia
Polyposis
Eosinophilic gastroenteritis
Amyloidosis
Mastocytosis
Lymphoma
Metastases

47

Which segment of small bowel has best prognosis if affected in crohns? Which has highest rate of complication

Distal small bowel

Ileocolic has highest rate of complciation

48

Localized fold thickening in the proximal small bowel suggests what

Infection (giardiasis, whipple)

49

Who is prone to giardia infection?

hypogammaglobulinemia

50

How does giardia present radiographically

Nodular fold thickening, increased secretions, spasm/rapid transit

51

Malabsorption, arthralgia, lymphadenopathy, abdominal tenderness, increased skin pigmentation

Whipple

52

Why is the PAS positive in whipple

glycoprotein deposited in macrophages of the lamina propria

53

What is a key feature of whipple disease?

Lack of hypersecretion, dilation, or distal bowel involvement

54

What non GI CT findings helps suggest whipple disease?

Sacroilitis

low attenuation LN

55

What is the pathology of lymphangectasia?

What is the usual radiogarphic presentation

Dilated lymph channels in the lamina propria and submucosa of bowel wall with associated enlarged villi

Channels may rupture and spill into lumen causing barium dilution

Thickened folds with nodules
or
Nodular filling defects

56

Tx of lymphangectasia?

Medium chain triglycerides

57

innumerable uniform nodular filling defects throughout small bowel

nodular lymphoid hyperplasia

58

What is nodular lymphoid hyperplasia usually associated with?

deficiency of IgA or IgM

59

Usual presentation of nodular lymphoid hyperplasia? Main DDx?

Innumerable, UNIFORM

60

GIve a DDx for terminal ileal discrete ulcerations.

Crohns
Infection (yersiniosis, amebiasis, TB)

61

What stones are crohns patients have increased risk of?

Cholesterol gallstones and oxalate renal stones

62

What is the string sign? Where is it seen most commonly?

Fixed narrowing with short segmental stricture from intramural fibrosis of crohns. Terminal ileum most commonly affected.

63

Circumferential asymmetry is suggestive of what dx?

Crohns

64

Differentiate yersinia/salmonella from crohns of the TI?

Yersinia/salmonella can have superficial erosions and fold thickening WITHOUT strictures

65

What is creeping fat

Fibrofatty changes in the mesentery adjacent to bowel wall thickening - seen with crohns

66

How/where does recurrent crohns occur?

Irregular countouring and nodular ulceration of the neoterminal ileum.

67

Differentiate active vs inactive crohns

Active - soft tissue density or contain a central water density ring

Inactive - Fat within the bowel wall (may be due to corticosteroid use)

68

DDx for thick small bowel wall with submucosal edema

Ischemia
Crohns
Lymphoma
Radiation enteritis
ACE-I induced

69

What helps differentiate intramural vs intraluminal gas

Intraluminal will be nondependent

Intramural will be nondependent and POSTERIOR and DEPENDENT because it is within the wall

70

name 4 conditions associated with pneumatosis intestinalis

Ischemia
Scleroderma
Corticosteroid use
COPD

71

What is a closed-loop obstruction

Mechanical small bowel obstruction in which blood supply to the loop can be compromised

72

What are the signs of closed loop obstruction

Bowel thickening, vascular engorgement, mesenteric stranding, differential perfusion loop

73

Small bowel and mesentery encircle the SMA in a whorl pattern in what condition

Midgut volvulus

74

What is the moulage sign?

"molded" or "casted" structure - resembles a tubular cast with paucity of mucosal folds

seen with Celiac

75

Featureless ileum with excessive intraluminal fluid obscures with moulage sign

Celiac disease

76

Loss of jejunal fold pattern and flocculation with segmentation of barium

Sprue

77

What are the three types of sprue?

Non tropical (gluten sensitive) -- adult and childhood

Tropical

78

What are the radiologic features of sprue

Hyper secretion - excess intraluminal fluid
Clumping and segmentation of barium
Thickened folds

79

tubular and featureless jejunum with focal stricture?

Sprue - can develop stricture due to ulcerative jejunoileitis

80

Name 6 associated conditions with celiac disease

Hyposplenism
Cavitary lymph node syndrome
Carcinoma
Lymphoma
Immunoglobulin A deficiency
Dermatitis herpetiformis

81

What part of the GI system does TB affect

Distal small bowel and cecum

82

What are the findings of GI TB

Ulcerations
luminal narrowing with segmental involvement
wall thickening
fistulas
shrunken and deformed cecum

83

Prolonged coating of affected bowel segments with barium for several days after the examination

Graft vs host disease

84

What are the two main regions of rotation of intestine during fetal life

Duodenum-jejunum

Cecocolic

85

What are the different types of malrotation

Nonrotation - small bowel in right hemiabdomen, colon in left

Incomplete rotation - incorrect location of cecum

Incomplete mesenteric fixation - mobile cecum

86

What are the 3 main complications of malrotation

Midgut volvulus/Obstruction

Congenital diaphragmatic hernia

Omphalocele

87

What is the consequence of small bowel diverticula

Usually asymptomatic

Occasionally lead to bacterial overgrowth

88

Hyperenhancement of bowel wall, kidneys, and adrenals

Small or collapsed inferior vena cava

Hypoperfusion complex

89

What is a meckels diverticulum

Remnant of the omphalomesenteric duct

90

Which tracer is used in a meckels scan

Technetium pertechnetate

91

What organs normally take up TcPertechnetate

Stomach, salivary glands

92

DDx for Atrophic featureless bowel folds

GVHD
Chronic ischemia
Celiac disease
Radiation enteritis
Amyloidosis
Infectious