Transanal opening of intersphincteric space (TROPIS) - A new procedure to treat high complex anal fistula

Abstract

Background: The sepsis in intersphincteric space has important role in pathogenesis of most complex fistula-in-ano. This sepsis is like a small abscess in a closed space. This closed space needs to be drained adequately and then kept open for the fistula-in-ano to heal properly. The aim was to lay open and drain the intersphincteric space through internal opening via transanal approach. This has been tried in submucosal and intersphincteric rectal abscesses but has never been tried in complex fistula-in-ano.

Materials and methods: All consecutive patients of complex high (involving >1/3 of sphincter complex) fistula-in-ano who were operated were included in the prospective cohort study. Preoperative MRI scan was done in all the patients. Transanal laying open of the intersphincteric space (TROPIS) was done through the internal opening. The external sphincter was not cut. The tracts in the ischiorectal fossa were curetted and cleaned. The incontinence scores were measured.

Results: 61 patients with high complex fistula-in-ano were included (follow-up:6-21 months). Male/Female:59/2, age-42.3 ± 9.5 years. 85.2% (52) were recurrent, 83.6% (51) had multiple tracts, 36.1% (22) had horseshoe tract, 34.4% (21) had supralevator extension and 26.2% (16) had associated abscess. 95.1% (58) were posterior fistula out of which 90.2% (55) were in posterior midline. Nine patients were excluded (due to tuberculosis, lost to follow-up). Fistula healed completely in 84.6% (44/52) and didn't heal in 15.4% (9/52). 4/9 of these were reoperated and fistula healed in three patients. Thus overall healing rate was 90.4% (47/52). There was no significant change in incontinence scores.

Conclusions: TROPIS is a simple effective sphincter sparing procedure to treat high complex fistula-in-ano including supralevator and horseshoe fistula.

Keywords: Anal; Fistula; Fistula-in-ano; Incontinence; Intersphincteric; Sepsis; Supralevator.