Fistula Laser Closure (FiLaC™) for fistula-in-ano—yet another technique with 50% healing rates?

Purpose: Treatment of ano-cutaneous fistulas remains a therapeutic challenge. Fistula Laser Closure (FiLaC™) is a relatively new technique for the treatment of ano-cutaneous fistulas. This study aimed to determine the success rate of fistula closure using FiLaC™. Secondary endpoints included adverse events and patient characteristics associated with treatment success. Methods: This was a retrospective cohort study of consecutive patients subjected to FiLaC™ at Digestive Disease Center, Bispebjerg University Hospital, Copenhagen, between March 2017 and July 2019. All patients had a one-track fistula not suitable for fistulotomy. All were treated with a draining seton for at least 8 weeks prior to laser closure. Fistulas were ablated with a 360-degree emitting 12-watt 1470 nm laser probe. The inner fistula opening was closed with absorbable suture. All patients were followed with clinical examination including MRI or EAUS 1 year after the procedure. Results: In total, 66 patients with 68 fistulas were included. Two patients had a high intersphincteric, 20 had low transsphincteric, 41 high transsphincteric and 5 had suprasphincteric fistulas. Fistula aetiology was cryptoglandular in 83.8%, whereas the rest were due to Crohn’s disease. Thirty-one (45.6%) were subjected to a second FiLaC™ procedure. Follow-up was median 19 months (12–26 months). Ultimately, 30 of 68 (44.1%) of the fistulas healed. No cases of incontinence following FiLaC™ were observed, but a single patient developed an abscess. Conclusion: Fistula closure with FiLaC™ had success rates comparable to that of other sphincter-sparing techniques. The technique seems safe with respect to adverse events and risk of incontinence.