Subtotal colectomy for treatment of acquired megacolon in the dog and cat.

The case records of 4 cats and 1 dog with megacolon and constipation were reviewed to study the history, clinical signs, pathologic changes, and longterm results of surgical treatment. The 4 cats had idiopathic megacolon. The dog had megacolon secondary to dietary indiscretion. All animals had radiographic evidence of a large colon, which was confirmed by exploratory coeliotomy. Two of the cats and the dog had an intraoperative finding of megacecum as well. Subtotal colectomy was performed in all cases, with the ileocolic valve being removed in 3 of these cases. End-to-side anastomosis was used to restore the integrity of the bowel. All animals were treated successfully with this surgical technique, as judged by clinical response and owner satisfaction. Histologically, there were no consistent lesions to explain the cause of this disease in the cats.