A randomized controlled trial of trans-intersphincteric double seton (TRISDS) for the treatment of perianal abscess

Incision and drainage (I&D) for perianal abscesses is associated with high rates of fistula formation. Our study aimed to evaluate the effectiveness of a novel technique, trans-intersphincteric double seton (TRISDS), designed to preserve anal sphincter integrity and improve clinical outcomes compared to I&D.

This prospective, randomized, non-blinded controlled study included adult patients with perianal abscesses located below the levator ani muscle with an internal opening. Patients were randomly assigned to either the TRISDS group (n = 55) or the I&D group (n = 51). The TRISDS technique involved two incisions: intersphincteric and drainage incisions with the placement of two loose setons. One seton was positioned to preserve the internal anal sphincter and facilitate drainage through the intersphincteric space, while the other seton aimed to protect the external anal sphincter to ensure comprehensive drainage. The I&D group underwent conventional I&D without damaging the anal sphincter complex. The primary outcome was the cure rate of perianal abscesses, which was defined as complete epithelialization of wounds without fistula or exudate and no recurrence within 12 months after surgery.

The TRISDS group achieved a significantly higher cure rate of 78.2% (43/55) compared to 41.2% (21/51) in the I&D group (P < 0.05). There were no significant differences in anal function at 2 months postoperatively between the groups (median Wexner score, IQR: 1.0 [0.0-1.0] vs 1.0 [0.0-1.0], P > 0.05).

The study highlighted the effectiveness of TRISDS in improving cure rate without compromising anal function. The TRISDS technique represents a promising strategy for the treatment of perianal abscesses. Further multicenter studies are recommended to validate these findings and expand the application of TRISDS in diverse patient populations.