[Our new operative method for high-type anorectal malformations based on the histological studies].

From 1971 onwards we have been examining the anatomy and histology of sphincter components in patients with several anorectal malformation who died of associated anomalies. These histological studies demonstrated that not only puborectal muscle but also the superficial and deep external sphincters exist, even in the high type anomalies, and that the mass of external sphincter is located above the anal dimple. Moreover, the inner circular muscle of rectum is thickened at the level of the closest part to the fistula. Based on our histological studies, we devised our new operation to use all the sphincter musculature effectively for the newly reconstructed anal canal. Our new surgical procedure is clearly different from Kiese wetter-Rehbein's method in that the puborectal muscle is penetrated from the outside of rectal wall and might be damaged, since puborectal muscle is attached to the blind pouch of rectum. Moreover, the puborectal muscle and the external sphincters can be easily identified by electrical stimulation under direct vision from extended sacroperineal approach. And the colon can be pulled exactly through the centre of the external sphincters and puborectal muscle under direct vision without causing any damage to these important sphincters, unlike Pena's operation.