Postoperative evaluation of fecal continence after sphincter-preserving operations for rectal cancer.

Seventy-eight sphincter-preserving operations for rectal cancer were evaluated from the viewpoint of postoperative fecal continence. Operative procedures consisted of 39 anterior resections and 39 pull-through operations and Maunsell-Weir's operation. Postoperative fecal continence was evaluated by questionnaires and anorectal examinations including (1) the distance from the anal verge to the anastomosis, (2) the length of sensation to light touch in the anal canal, (3) electromyography of the sphincter, (4) internal sphincter reflex (5) pressure profile of the anal canal, and (6) barium enema radiography. Patients' evaluations of their continence were good when the distance of the anastomosis was over 5 cm from the anal verge, and mostly poor under 3 cm. Good or fair evaluations were obtained when the internal sphincter reflex or high pressure zone of the anal canal were preserved. Size of the reservoir was measured using a planimeter on the lateral view of the barium enema up to 6 cm from the upper margin of the anal canal. Good or fair evaluations were obtained when size was 30 cm2.