This retrospective study compared the radiographic appearance of small and large intestines of cats with various medical conditions while creating a quantitative index for interpretation of intestinal diameters on abdominal radiographic views. The abdominal radiographs of 74 cats were evaluated as part of the study. The cats were assigned to 1 of 4 categories: no gastrointestinal tract disease, nonobstructive gastrointestinal disease, linear foreign body (LFB), and small intestinal mechanical obstruction not caused by an LFB. Different measurements in millimeters were compared such as the maximum and minimum external small intestine diameter (SID) and colon diameter (CD). The dorsoventral height measurements from lateral radiographic views of the cranial end plate of L2 (VEL2) and L5 (VEL5) vertebrae were also compared. When the maxSID:VEL2 ratio was >2.0, gastrointestinal disease was present. At the maxSID:VEL2 ratio of >2.5, the most likely abnormality was intestinal obstruction and a ratio >3.0 had a > 70% likelihood of intestinal obstruction. Plication of the small intestines was significantly related to LFB and all 10 cats with plication had conditions that required abdominal surgery. There was no correlation between presence of gas in the small intestine and disease, though all 5 cats that had a combination pattern of linear and comma shaped gas had surgical disease. It was noted that a comma-shaped gas pattern is nearly always an abnormal radiographic finding, but it is not pathognomonic for a LFB. [VT]
Baez J, Hendrick M, Walker L et al: Radiographic, ultrasonographic, and endoscopic findings in cats with inflammatory bowel disease of the stomach and small intestine: 33 cases (1990-1997), J Amer Vet Med Assoc 215:349, 1999.