Sphincter-saving therapy for fistula-in-ano: long-term follow-up after FiLaC.

Background: The treatment of anal fistula remains a challenge between maintaining continence and radical surgery to prevent recurrence. Fistula-tract Laser Closure (FiLaC) is a sphincter-saving technique using a radial emitting laser fibre to close the fistula tract. The aim of this study was to report long-term outcomes in patients who received FiLaC therapy for transsphincteric and intersphincteric anal fistula between January 2011 and December 2017.

Methods: A retrospective study was performed on patients who were treated with FiLaC- for a transsphincteric and intersphincteric anal fistula at our institution between January 2011 and December 2017. In all patients, the FiLaC procedure was combined with a closure of the internal orifice using a simple 3-0 Z stitch. Patient characteristics, previous proctological history, healing rates, failures and postoperative continence were investigated.

Results: The study included 83 patients [mean age 50.01 ± 14.59 years. 64 (77.1%) males] with a mean follow-up period of 41.99 (± 21.59) months (range 4-87 months). Thirteen patients (15.7%) had a recurrent fistula. 65 patients (78.3%) had undergone prior abscess drainage with insertion of a seton. The primary healing rate was 74.7% (62 of 83 patients) overall. Eleven (13.3%) of the 21 patients (25.3%) who failed FiLaC-therapy underwent a second operation. In eight cases, Re-FiLaC and in three cases, fistulectomy with closure of the internal orifice was performed. Afterwards 6 (54.5%) of these 11 patients could be considered cured: 3 who had fistulectomy and three who had Re-FiLaC treatment. The overall healing rate after second FiLaC was 78.3% (65 of 83 patients) while the overall healing rate for FiLaC therapy combined with any second procedure was 81.9% (68 of 83 patients). The follow-up period in this group of 11 patients who received re-operation was 38 months (range 13-84 months). Changes in continence occurred in eight patients (9.6%). No patient reported major incontinence postoperatively.

Conclusions: The FiLaC procedure is associated with good healing rates in long-term follow-up and should be considered as a treatment option for transsphincteric and intersphincteric anal fistulae, especially due to the low complication rate and low risk of sphincter injury.