Ex 1 - Small Bowel Flashcards
(25 cards)
Standard Views - intestines
Lateral recumbent
VD
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
Fundamentals of radiographic evaluation - small intestine
- size and shape
- position
- margination
- opacity
- motility
Distended bowel is seen with…
inflammatory conditions, partial and total obstructions
Two causes of obstruction - need to differentiate (sm intestine)
Mechanical
Functional
Repeatability
Want to see a suspicious area on MULTIPLE rads over time to increase significance of the finding
Ileus
Disruption of normal propulsive ability of the GI tract
- Mechanical or Functional
- occur in dogs and cats
- should be differentiated prior to sx
Functional ileum
“paralytic ileus”
- Peristaltic contractions of the bowel cease
- lumen remains patent
- usually gas filled loops
- stress, electrolyte imbalances, pain, etc - causes
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
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
Patterns of enlargement - small intestine
- Focal involvement, mild distention
- Focal involvement, severe distention
- General involvement, mild distention
- General involvement, severe distention
Focal involvement, mild distention
mild increase in size of the small bowel
regional enteritis, regional peritonitis, partial mechanical obstruction, early functional ileus
Focal involvement, severe distention
think mechanical obstruction
FB, intussusception, neoplasia, stenosis, stricture, dysautonomia, parvo
General involvement, mild distention
functional ileus, enteritis, drugs rxn, malabsorption
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)
Normal position of small intestine
evenly distributed throughout the abdomen
Position of small intestine - obese cats
the right ventral abdomen
Where do hernias occur? (7)
Diaphragmatic Peritoneo-pericardial Body wall Inguinal Scrotal Umbilical Perineal
Some reasons for decreased serosal detail? (5)
Juveniles Emaciated patients Ascites Peritonitis Carcinomatosis
Can you determine intestinal wall thickness on survey rad?
No! its unreliable
Gravel sign
Opaque granular material
Caused by chronic partial obstruction –> desiccation of the ingest that is trapped proximal to the obstruction
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
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
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
