Transanal Advancement Flap Repair of Transsphincteric Fistulas W. R. Schouten, M.D., D. D. E. Zimmerman, J. W. Briel, M.D. From the Colorectal Research Group of the Department of Surgery, Erasmus Medical Center, Rotterdam, the Netherlands OBJECTIVE: The purpose of this study was to evaluate the healing rate of transsphincteric perianal fistulas after transanal advancement flap repair and to examine the im- pact of this procedure on fecal continence. METHODS: Between January 1992 and January 1997, 44 consecutive patients with a transsphincteric perianal fistula passing through the middle or upper third of the external anal sphincter underwent transanal advancement flap repair. There were 34 male patients, and the median age was 44 (range, 19-72) years. Twenty-four patients (55 percenO had previously undergone one or more prior attempts at repair. With the patient in prone jackknife position, the internal opening of the fistula was exposed using a Parks retractor. The crypt-bearing tissue around the internal opening and the overlying anoderm was excised. A layer of mucosa, submucosa, and internal sphincter fibers was mobilized 4 to 6 cm proximally. The base of the flap was approximately twice the width of its apex. The flap was advanced and sutured to the anoderm below the level of the internal opening. The median follow-up was 12 months. Fecal con- tinence was evaluated in 43 patients by means of a ques- tionnaire. RESULTS:Transanal advancement flap repair was successful in 33 patients (75 percent). Success was in- versely correlated with the number of prior attempts. In patients with no or only one previous attempt at repair the healing rate was 87 percent. In patients with two or more previous repairs the healing rate dropped to 50 percent. In 15 patients (35 percent) continence deteriorated after transanal advancement flap repair. Twenty-six patients (59 percent) had a completely normal continence preopera- tively. Ten of these patients (38 percent) encountered soft- ing and incontinence for gas after the procedure, whereas three subjects (12 percent) complained of accidental bowel movements. Eighteen patients (41 percent) had continence disturbances at the time of admission to our hospital. In two of these patients (11 percent), incontinence deteriorated. CONCLUSIONS: The results of transanal advancement flap repair in patients with no or only one previous attempt at repair are good. In patients who have undergone two or more previous attempts at repair the outcome is less favor- able. Remarkably, the number of previous attempts did not adversely affect continence status. [Key words: Transsphinc- teric fistula; Transanal advancement flap; Fecal incontinence] Schouten WR, Zimmerman DDE, Briel JW. Transanal ad- vancement flap repair of transsphincteric fistulas. Dis Colon Rectum 1999;42:1419-1423. F or many years transsphincteric perianal fistulas were treated by laying open the entire fistulous tract. A major disadvantage of this technique is the Read at the meeting of The American Society of Colon and Rectal Surgeons, San Antonio, Texas, May 2 to 7, 1998. No reprints are available. inevitable transsection and subsequent separation of both sphincters. Although incontinence for solid stool is rare, the reported incidence of minor continence disorders such as soiling, incontinence for gas, or liquid stool is high, varying between 30 and 50 per- cent.l, 2 It has been suggested that the separation of both sphincters is less pronounced after muscle divi- sion by a staged seton technique. However, the re- ported incidence of impaired continence after this procedure is remarkably high, varying between 40 and 60 percentP -5 Until now it is unknown which treatment modality is superior, because prospective, randomized trials comparing the lay-open technique and the staged seton technique are lacking. In recent years the transanal advancement flap repair (TAFR) has been advocated as an attractive alternative for patients with transsphincteric perianal fistulas. It has been stated that this procedure is advantageous be- cause it enables the healing of almost all fistulas without sphincter damage and without continence disturbance. Recently, however, less favorable results have been reported in patients with a transsphincteric fistula of cryptoglandular origin. 6 To investigate the healing rate after TAFR and its impact on fecal conti- nence we conducted a prospective study. PATIENTS AND METHODS From January 1992 to January 1997, 44 consecutive patients with a transsphincteric fistula of cryptoglan- dular origin underwent TAFR. In all patients the fis- tulous tract crossed the middle or upper third of the external anal sphincter. The present study comprised ten women. Median age at the time of repair was 44 (range, 19-72) years. Thirty-five patients (80 percent) had previously undergone one or more attempts at repair before referral to our hospital. Patients with a superficial transsphincteric fistula, passing through the lower third of the external anal sphincter, under- went a lay-open procedure and were excluded from this study. Subjects with a perianal fistula caused by Crohn's disease were also excluded. All patients un- 1419