Transanal Opening of Intersphincteric Space for Fistula-in-Ano

The role of the intersphincteric space in the pathogenesis of fistula-in-ano is being increasingly recognized. Submucosal and intersphincteric rectal abscesses have been surgically managed by laying open and draining the intersphincteric space as well as by the modified ligation of intersphincteric fistula tract (LIFT) procedure. In 2017, the transanal opening of intersphincteric space (TROPIS) technique was reported for the treatment of high, complex anal fistulae.

We aim to investigate the advantages of performing the TROPIS procedure in patients with fistula-in-ano.

This was a prospective cohort study investigating the outcomes in patients who had undergone a procedure using the TROPIS technique for the treatment of fistula-in-ano. Preoperative magnetic resonance imaging scans and electronic colonoscopies were performed on all patients. A clinical database evaluating the following variables was constructed: age, gender, body mass index (BMI), previous fistula surgery, type of fistula, postoperative complications, duration of follow-up, success rate, and incontinence scores pre- and postoperatively.

The TROPIS procedure was performed on 41 patients with fistula-in-ano with a follow-up time of 6-23 months. The characteristics of the patients were as follows: 36 males, 6 females, mean age 38.6±13.2 years, and mean BMI 23.5±3.9 kg·m^-2. All patients (41) had transsphincteric fistulae, and 90.2% (37) had high fistula. Of the 41 patients, 22% (9) had recurrent fistulae, 29.27% (12) had horseshoe fistulae, 7.3% (3) had supralevator fistulae, and 14.6% (6) had an associated abscess. The fistula healed completely in 85.3% (35) of patients and failed to heal in 14.7% (6) of patients, and the healing of high fistula was 86.5% (32). Of those patients who had not healed completely, 2 were found to have contracted iatrogenic infections due to foreign residues and underwent surgery with the passing of a loose seton. The additional 4 patients who had not healed underwent a fistulotomy and healed completely thereafter. There were no significant changes in incontinence scores. The incontinence scores were .15 ± .36 preoperatively and .22 ± .47 3 months postoperatively (t = -1.438, P = .16).

The TROPIS technique is a novel sphincter-preserving procedure, which can be effectively used in treating fistula-in-ano.