Intraluminal measurement of distance in the colorectal region employing rigid and flexible endoscopes.

Intraluminal measurements of distance cephalad to the anal verge in the colorectal region of 40 consecutive adult patients were performed employing rigid and flexible proctosigmoidoscopic techniques. In 2/40 (5%) patients, the measurements were identical. In 32/40 (80%) patients, measurements employing a flexible proctosigmoidoscope exceeded measurements employing a rigid instrument by at least 3 cm. The observations have relevance in the context of assessments of adequate distal margins and preservation of anal continence in patients requiring colorectal surgery via transabdominal, transsacral, transperineal, and/or transanal routes.