FIELD: medicine.SUBSTANCE: invention refers to medicine, namely to surgery and coloproctology. Transsphincteric fistula is transferred into intrafincteric fistula. Transverse incision 1.5 cm long in a medial edge of the fistulous passage at distance of 1.5 cm from the edge of the anal ring. Skin is dissected with subcutaneous fat, fistulous passage is separated within 1.0 cm without exposing its lumen. Two ligatures are used to tie a fistulous passage； a fistulous passage is dissected between the ligatures； a fistiform altered tissue in the form of a triangular flap is excised in the area of the internal opening of the fistulous passage in the involved crypt of the anal canal. Then, transverse incision 0.2 cm above an internal fistulous passage is used to cut out a mucous membrane on pedicle 1.5 cm long and 0.8 cm wide, which is laid without tension on the inner opening of the fistulous passage and fixed with 3 sutures to the flap edges, and the mucous defect remaining after movement is closed with 2 interrupted sutures. Wound is closed with medical glue "Sulphacrylate", the wound area is additionally covered with haemostatic sponge. Outer opening of the fistulous passage is sanitized daily with antiseptics for 3 days； 3 % alcohol solution of iodine or 70 % ethyl alcohol is introduced into the lumen.EFFECT: method enables reducing length of treatment and rehabilitation of patients by 50 %, minimizing purulent complications and anal sphincter failure.1 cl, 1 ex, 1 dwgИзобретение относится к медицине, а именно к хирургии и колопроктологии. Переводят транс- в интрасфинктерный свищ. Поперечным разрезом длиной 1,5 см у медиального края свищевого хода, на расстоянии 1,5 см от края анального кольца. Рассекают кожу с подкожной клетчаткой, выделяют свищевой ход на протяжении до 1,0 см без вскрытия его просвета. Двумя лигатурами завязывают свищевой ход, между лигатурами свищевой ход рассекают, в области внутреннего отверстия свищевого хода у пораженной крипты анального канал
