A novel sphincter-sparing procedure for seton removal in complex perianal fistulas: the FiLaFlap technique

Background: Complex perianal fistulas present a significant surgical challenge due to high recurrence rates and the need to preserve sphincter function. Fistula-tract Laser Closure (FiLaC™) is a minimally invasive technique that offers promising results, but incomplete closure of the internal opening remains a major cause of recurrence. To improve outcomes, we propose the FiLaFlap technique, which combines FiLaC™ with a mucosal advancement flap to enhance fistula healing. Methods: We conducted a retrospective study of patients who underwent seton removal with the FiLaFlap procedure between January 2023 and September 2024. Postoperative data, including pain levels, complications, continence status, and follow-up outcomes, were collected prospectively. Patients underwent clinical evaluations and 3D endoanal ultrasound assessments at predefined intervals. Results: A total of 24 patients (58.3% male, mean age 39.4 ± 12.4 years) were included. The mean time between seton placement and FiLaFlap was 5.95 ± 1.78 months. Postoperative pain was low (VAS 2.20 ± 0.97), and no major complications occurred. At 6 months, 91.6% of patients achieved clinical remission, while 83.3% had ultrasound-confirmed healing. Only one patient reported minor incontinence. Conclusion: The FiLaFlap technique appears to be a safe and potentially effective sphincter-preserving strategy for complex perianal fistulas, demonstrating high remission rates with minimal morbidity. Further studies with larger cohorts and extended follow-up are needed to validate these preliminary findings.