Treatment of Complicated Anal Fistula by an Endofistular Polyurethane-Sponge Vacuum Therapy: A Pilot Study

Treatment of supra- and transsphincteric anal fistulas remains a clinical challenge because current treatment results are variable and potentially endanger sphincter function.

Based on positive results of endoluminal polyurethane-sponge vacuum therapy in the upper and lower GI tract, a new system for endofistular vacuum therapy was developed for anal fistulas to utilize vacuum therapy to remove the endofistular pseudoepithelium and to induce granulation in the fistula tract.

This study is based on a prospective case series.

Seven patients with complicated anal fistulas (3 associated with Crohn's disease and 4 of cryptoglandular origin) longer than 4 cm were treated. Initially, the fistula was curettaged and the first endofistular vacuum therapy sponge was positioned in the fistula tract. The inner fistula opening was closed by suture. A 125 mm Hg constant vacuum was applied to the sponge, and the endofistular vacuum therapy sponge was changed a median of 3 (3-5) times after each 48 to 72 hours of constant vacuum therapy. After final removal, the fistulas were reevaluated every other week for 3 months.

The main outcome measured was the closure of the fistula.

All patients tolerated the therapy well and no adverse events were observed. Fistula tract closure was demonstrated within 4 weeks after the termination of vacuum therapy. One patient with cryptoglandular fistula developed a recurrence within the follow-up of 3 months.

This was an observational study that had no control arm.

In this pilot case series, the results are encouraging. Because endoluminal vacuum therapy would be a new and sphincter-sparing therapy, this concept warrants further investigation in controlled trials.