Colonoscopy is a procedure that allows the inner lining (mucosa) of the colon to be evaluated with the use of a flexible endoscope. During colonoscopy, the endoscope is gently inserted first in the rectum, and then advanced into the colon. The entire colon is evaluated up to the cecum (similar to an appendix in a person) and the junction of the small intestine (this portion of the small intestine is called the ileum).
The mucosa is examined for disease, which may appear as diverticulum, polyps, masses, strictures or abnormal blood vessels. Abnormalities are biopsied and analyzed for inflammation and cancer by a veterinary pathologist.
Symptoms that your pet may be exhibiting to indicate that they may need a colonoscopy include difficulty defecating, chronic constipation, diarrhea or blood in the stool.
Left: This picture was taken during colonoscopy in a cat. The arrow points to the opening to the small intestine (ileum). The opening in the center of the picture is the cecum.
Right: This picture was also taken during colonoscopy in a cat. The arrow points to an irregular area in the lining of the colon that was biopsied and shown to be cancerous.