Ex 1 - Small Bowel Flashcards Preview

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Flashcards in Ex 1 - Small Bowel Deck (25):
1

Standard Views - intestines

Lateral recumbent

VD

2

Patient prep - Intestinal rads

* Stable patient with chronic GI signs
- NPO 12-24 hrs
- Cleansing enema 2-4 hrs prior (if possible)

* Pt with acute abdomen, vomiting, or palpably enlarged bowel
- NO specific prep necessary
- abnormal pattern of fluid and gas can help make dx

3

Fundamentals of radiographic evaluation - small intestine

1. size and shape
2. position
3. margination
4. opacity
5. motility

4

Distended bowel is seen with...

inflammatory conditions, partial and total obstructions

5

Two causes of obstruction - need to differentiate (sm intestine)

Mechanical

Functional

6

Repeatability

Want to see a suspicious area on MULTIPLE rads over time to increase significance of the finding

7

Ileus

Disruption of normal propulsive ability of the GI tract

* Mechanical or Functional
- occur in dogs and cats
- should be differentiated prior to sx

8

Functional ileum

"paralytic ileus"

- Peristaltic contractions of the bowel cease
- lumen remains patent
- usually gas filled loops

* stress, electrolyte imbalances, pain, etc - causes

9

Mechanical ileum

"Two populations of bowels"

- caused by PHYSICAL obstruction
- non-uniform distention of the bowel
- over time, will become paralytic --> resulting in uniform distention

* FB, intussusception, neoplasia and strictures - causes

10

Mechanically obstructed bowel differs from functionally obstructed bowel

- usually of larger diameter than functional
- usually has mixture of gas and fluid; functional has more gas or may be completely gas-filled
- usually has some normal sized bowel present; functional may have generalized involvement

11

Patterns of enlargement - small intestine

- Focal involvement, mild distention

- Focal involvement, severe distention

- General involvement, mild distention

- General involvement, severe distention

12

Focal involvement, mild distention

mild increase in size of the small bowel

regional enteritis, regional peritonitis, partial mechanical obstruction, early functional ileus

13

Focal involvement, severe distention

think mechanical obstruction

FB, intussusception, neoplasia, stenosis, stricture, dysautonomia, parvo

14

General involvement, mild distention

functional ileus, enteritis, drugs rxn, malabsorption

15

General involvement, severe distention

Functional: loops will be uniformly distended (mesenteric torsion)

Mechanical: loops not uniform, some may be normal
(complete obstruction of distal bowel, intestinal volvulus, intussusception, FB, neoplasia, recent abdominal sx)

16

Normal position of small intestine

evenly distributed throughout the abdomen

17

Position of small intestine - obese cats

the right ventral abdomen

18

Where do hernias occur? (7)

Diaphragmatic
Peritoneo-pericardial
Body wall
Inguinal
Scrotal
Umbilical
Perineal

19

Some reasons for decreased serosal detail? (5)

Juveniles
Emaciated patients
Ascites
Peritonitis
Carcinomatosis

20

Can you determine intestinal wall thickness on survey rad?

No! its unreliable

21

Gravel sign

Opaque granular material

Caused by chronic partial obstruction --> desiccation of the ingest that is trapped proximal to the obstruction

22

Rad Findings - Focal Neoplasia (7)

Straightened border
Thickened wall
Peristalsis will be decreased
Lumen is narrowed
Mucosa can be irregular (ulceration)
+/- Distended on the oral sign
"Apple core" sign

23

Rad Findings - Infiltrative Neoplasia (2)

*Often affect a large section of bowel (e.g. lymphoma)
- narrowed lumen
- irregular mucosa

*Biopsy is necessary to differentiate LSA from IBD

24

Rad Findings - FB (2)

*Total or partial obstructions

*Total obstructions
- greater distention of the bowel orally
- no passage of +contrast past the FB
- contrast medium should be seen to outline the FB which will create a filling effect

25

Why would you see plication? (accordion shape)

With a Linear Foreign Body

*Also see abnormal "C-shaped" discontinuous gas bubbles (dogs > cats)