Modified Sphincter-Preserving Operation for Anal Fistula

Abstract

Conventionally, low intersphincteral fistulas have been operated on by incising the internal sphincter muscle and eliminating the primary opening and primary lesion. Suturing is then performed, and the fistular canal is eliminated from the secondary opening to the subcutaneous external sphincter. With this technique, recurrence is seen in 2% or less of the cases, but there are some rare cases of failure of the suture of the muscle. For this reason, the author recently switched to a technique in which the internal sphincter muscle is incised and only the primary opening is eliminated. Suturing is then performed, and the primary lesion and fistular canal are eliminated by coring out from the secendary opening.
In the case of ischiorectal fistulas, the space formed after elimination of the primary opening and primary lesion is subjected to sphincter filling up. Recurrence is seen in 2% or less of these cases, but there are some cases of recurrence due to suture failure at the sphincter filling up site. In order to prevent this, steps should be taken to achieve good drainage.