Abstract
This report describes the current status of the lay-open procedure, which is generally performed for the low transsphincteric anal fistulas that are most commonly seen in routine medical cases. The lay-open procedure involves incising the fistula from the primary opening to the primary focus (secondary opening), which is fundamental for radical treatment of an anal fistula.
However, the course of low transsphincteric anal fistulas can be complicated.
Therefore, surgery to preserve the anal sphincter or different treatment methods should be considered for cases of transsphincteric anal fistulas or preoperative anal function disorders. Sphincter-preserving treatments conducted in Japan and overseas are discussed and treatment outcomes are evaluated.
When performing surgery for treating anal fistula, both preoperative diagnosis and anal function assessment are extremely important, and an appropriate procedure should be selected considering both radical curability and anal function in each case.
