Treatment of anal fistulas with high intersphincteric extension

Abstract

Background: Intersphincteric fistulas with a high upward extension, up to or above the level of the puborectal muscle, in the intersphincteric plane are rare. Most of these fistulas have no external opening and they are frequently associated with a high intersphincteric and/or supralevator abscess. Division of a large amount of internal anal sphincter by extended fistulotomy has a potential risk of diminished fecal continence.

Objective: The aim of this study was to evaluate flap repair combined with drainage of associated abscesses in high intersphincteric fistulas.

Design: This study was performed as a retrospective review.

Settings: The study was conducted at the Division of Colon and Rectal Surgery, Erasmus MC, between March 1995 and February 2011.

Patients: Fourteen patients with a cryptoglandular fistula with high intersphincteric extension were included.

Interventions: Transanal advancement flap repair combined with intersphincteric and/or extrasphincteric drainage of associated abscesses was performed. Preoperatively, patients underwent endoanal MRI.

Main outcome measures: Healing was defined as complete wound healing with absence of symptoms. Patients were followed up to assess the recurrence rate and Rockwood fecal continence score.

Results: In 1 patient the fistula was not associated with an abscess. In 10 patients the fistula tract ended in a high intersphincteric abscess. Three patients presented with a high intersphincteric abscess and a supralevator abscess. Primary healing was observed in 79% of the patients. The 3 patients without primary healing had a supralevator abscess. In these patients, healing was obtained after a second, third, and fourth procedure. The overall healing rate was 100%. Median postoperative Rockwood score was 0 (range, 0-15).

Limitations: Retrospective design and lack of baseline continence data were the limitations of this study.

Conclusions: Since most high intersphincteric fistulas have no external opening and are frequently associated with abscesses, preoperative imaging is useful. Flap repair with adequate drainage of the abscesses is successful, except in fistulas with supralevator extension. However, healing may be achieved by additional procedures.