Diagnostic Imaging: The Abdomen

Question 1

List three times where the serosal detail of the peritoneal cavity may be poor on a radiograph

Answer 1

Young/thin
Peritonitis
Fluid
Neoplasia

Question 2

Where is the spleen usually seen on radiographs?

Answer 2

Head caudal to stomach on the left.
Tail usually mid-ventral abdomen on the lateral view.

Question 3

Where is the spleen usually seen on radiographs?

Answer 3

Head caudal to stomach on the left.
Tail usually mid-ventral abdomen on the lateral view.

Question 4

Describe the position of the splenic head.

Answer 4

Smooth triangle in the left cranial abdomen.
Caudal to the stomach
Cranial to left kidney.

Question 5

How may a splenic mass display on a radiograph?

Answer 5

Small intestine displaced - caudally or dorsally
May bleed so we can see free fluid or poor detail.

Question 6

Where can the ventral lobe of the liver usually be seen on an abdominal radiograph?

Answer 6

Approximately at the level of the costal arch (breed dependant)

Question 7

What measurement can be helpful to assess liver size?

Answer 7

Gastric axis: normal = perpendicular to spine, parallel to ribs.

Question 8

What is the long axis of the stomach parallel to?

Answer 8

Ribs

Question 9

List four pieces of information that you may get about the position of the stomach from plain radiographs

Answer 9

Hiatal hernia
Gastro-oesophageal intussusception
Diaphragmatic rupture
Dilation vs volvulus

Question 10

How can you tell whether a small intestine is dilated?

Answer 10

Ratio of width SI to height of mid-body of L5.
- SI:L5 < 1.4 - very unlikely to be obstructer
- SI:L5 > 2.4 - very likely to be obstructed
Ratio of width of largest and smallest loops
- <2 very unlikely to be obstructed
- >3.4 very likely to be obstricted

Question 11

What is a chronic partial obstruction?

Answer 11

Chronic build up of ingesta over time - contents looks like faeces but not in the colon.

Question 12

Describe the position of the ascending, transverse, descending colons and rectum.

Answer 12

Ascending - right mid-abdomen
Transverse - crosses caudal to the stomach
Descending - left abdomen
Rectum - within pelvic canal

Question 13

What size should the colonic width not exceed?

Answer 13

3 times that of the normal small intestine.
The length of the body of L7 - >1.5x likely to indicate dysfunction.

Question 14

How can you see if the size of a cat’s colon is normal and what would indicate a megacolon?

Answer 14

<1.3x length of L5 suggests normal
>1.5x length of L5 is good indicator of megacolon

Question 15

List 5 disadvantages of ionic water-soluble iodinated contrast media.

Answer 15

Irritant extra-vascularly.
Toxic in large doses.
Viscous
Contrindicated I/V in cardiovascular or renal insufficiency.
Contraindicated for myelography.

Question 16

List 3 disadvantages of non-ionic water-soluble iodinated contrast media.

Answer 16

Slightly more expensive
Viscous
Side-effects may still occur, although rare.

Question 17

What does arthrography look at?

Answer 17

Joints

Question 18

What does angiography look at?

Answer 18

Blood vessels

Question 19

What does fistulography look at?

Answer 19

Sinus tracts

Question 20

Which contrast media should you use in a suspected rupture?

Answer 20

Iodinated contrast

Question 21

What does a barium ‘follow-through’ study look at?

Answer 21

Evaulates stomach and small intestine

Question 22

When are the final images of a barium ‘follow-through’ study taken?

Answer 22

24 hours

Question 23

What structure does a barium enema evaluate?

Answer 23

Large intestine