The significantly higher recurrence rate in the intervention group led to a serious ethical consideration of a premature closing of the study which was decided due to safety and benefit concerns

This is a randomised controlled trial to evaluate the outcome of treatment of complex perianal fistula by Video-assisted anal fistula treatment (VAAFT) compared to fistulectomy and sphincter reconstruction as standard surgical procedure.

The surgical treatment of complex fistulas is difficult and ideally aims to completely heal the fistula and prevent recurrence without affecting the anal sphincter function. The definitive surgical treatment options include transsphincteric fistulectomy and sphincter repair, intersphincteric ligation of the fistula tract (LIFT), transanal advancement flap and cutting Seton suture. All the methods caries a relative high recurrence and complication rate including the risk of anal incontinence .Transsphincteric fistulectomy and primary reconstruction of the anal sphincter has been reported to have a healing rate between 90 - 95,8 %, recurrence rate of 7,1-9,7 % and 5-30 % experience incontinence in varying degree. Video-assisted anal fistula treatment (VAAFT) is a novel sphincter saving procedure for treating complex anal fistulas and recently introduced with promising early results with a healing rate of 74-87.1 % after 1 year. The procedure can be done as a day-case surgery with the ability of precise identification of the fistula tract, including the presence of secondary branches. The method includes an endoscopic debridement and closure of the internal opening. Only few scientific reports of the method has been published and only with short term results, and there is a need of validating the efficacy of this procedure in a prospective randomized trial. There are few randomised controlled trials in the literature on the treatment of complex anal fistulas treatment and there is no conclusive evidence of which method is the best. Furthermore the knowledge of changes in quality of life and functional results in terms of standardized continence evaluation and manometric studies are either contradictive or simply lacking after the surgery for anal fistulas. The aim of this study is to conduct a randomized clinical trial to compare VAAFT (mini invasive and sphincter-saving) with the traditional transsphincteric fistulectomy and primary reconstruction in terms of recurrence rate, manometric and functional changes as well as changes in quality of life.

Inclusion Criteria:

• Patients with complex transsphincteric anal fistulas >18 yrs old.

Exclusion Criteria:

• Crohns fistulas
• Signs of suppuration or/and branching.
• Malignancy within 5 yrs.
• Previous radiotherapy of the abdomen and pelvis.
• Current Immune- suppressive treatment.