Use of the seton in the treatment of extrasphincteric anal fistula.

Ten extrasphincteric fistulas have been treated by the two-stage seton procedure. The seton was left in situ for three months; follow-up varied from six months to 2 1/2 years. There were no recurrences. Six patients experienced slight soiling and one patient became incontinent. Provided that only muscle tissue is enclosed by the seton, the procedure gives good results; a diverting colostomy is not necessary.