TAMIS-flap technique: full-thickness advancement rectal flap for high perianal fistulae performed through transanal minimally invasive surgery

Introduction The formation of an advancement rectal flap could be technically demanding in the presence of high perianal of rectovaginal fistula, and the outcomes could be frustrated by inadequate view, bleeding and a poor exposure through the standard transanal approach. The application of the transanal minimally invasive surgery (TAMIS) to the advancement rectal flap procedure could overcome these difficulties. Technique In lithotomy position, a partial fistulectomy and a curette of the internal orifice were performed. The internal opening was closed on the anal sphincter plane. The dissection of the full thickness flap commenced through the classic transanal approach. The TAMIS port was inserted and the mobilization of the flap was continued proximally for as long as required. The laparoscopic visualization allowed a perfect view, a proper orientation of the flap and an accurate hemostasis. In order to avoid an excessive traction to the sutures, the length of the flap should be approximately twice as long as the distance of the internal orifice from the dentate line. Results Since November 2015, four patients with a recurrent high perianal fistula (median distance from the dentate line was 4.8 cm) underwent a TAMIS-flap procedure. The operation was performed at a median time from the diagnosis of 19 months. The median operative time was 115 minutes (range 90-150). No complications were recorded. Conclusions The TAMIS-flap procedure seems a promising technique to perform a safe dissection when a long advancement rectal flap is necessary to treat a high perianal or rectovaginal fistula. The use of laparoscopic instruments and the continuous pneumorectum allow to maintain an adequate visualization and to avoid complications that could negatively affect the outcomes of the procedure.