Colonoscopic features of colonic anastomoses.

Colonic anastomoses are frequently encountered, but their endoscopic features have never been adequately characterized. Results of 117 consecutive colonoscopies in patients with colonic anastomoses were prospectively studied during a 12-month period. Anastomoses were photographed, videotaped, and reviewed by the authors. The age range of patients was 18 to 87 years, and interval from surgery extended to 42 years. An equal number of right and left colonic resections were encountered; 9 patients had subtotal colectomies. Ninety-two anastomoses were hand-sewn, and 25 were stapled. Ileal pouch-anal anastomoses were not included. Nine common anastomotic features were identified with the following frequency of occurrence: neovascularity, 105 (89.7%); white anastomotic edge, 64 (54.7%); disruption of haustral pattern, 64 (54.7%); radial suture tracks, 35/92 (38.0%); exposed suture, 11/92 (11.9%); exposed staples, 6/25 (24%); scar tissue adjacent to anastomotic line, 8 (6.8%); nondistensibility of anastomosis, 5 (4.3%); blind colonic pouch, 10 (8.5%). No recurrent carcinomas were noted. The site of seven anastomoses (5.5%) could not be identified. Six of these patients underwent endoscopy more than 8 years postoperatively. Of the remaining 110 patients, 94 (85.5%) had between two and four of the above features identified. In three of four patients who required dilation because of strictures, neovascularity was not seen. We conclude that colonic anastomoses have characteristic endoscopic features. These features can be used as landmarks for definitive identification of anastomotic sites at colonoscopy. The lack of neovascularity at a colonic anastomosis may be an indicator of relative ischemia, predisposing to stricture formation.