Open Fistulectomy vs. Laser Closure for Low Perianal Fistula

August 27, 2026 updated by: Nada Mohamed Abd El Meged, Assiut University

Open Fistulectomy Versus Fistula Tract Laser Closure in Low Perianal Fistula

Perianal fistula is an abnormal tunnel connecting the anal canal to the perianal skin, frequently causing chronic pain, discharge, and impaired quality of life. Traditional open fistulectomy is an established treatment with high healing rates, but it leaves an open wound that requires prolonged recovery and carries a risk of anal sphincter injury. Fistula-tract Laser Closure (FiLaC) is a minimally invasive, sphincter-preserving technique that uses laser thermal energy to close the tract from within while minimizing tissue trauma.

This study is a prospective, randomized controlled trial designed to compare the efficacy and safety of open fistulectomy versus laser fistulotomy in adult patients with primary low perianal fistula.

Participants are randomly assigned to one of two surgical treatment groups:

  • Group 1: Laser fistulotomy (FiLaC) using a 1470 nm diode laser probe to seal the tract, combined with internal opening closure.
  • Group 2: Conventional open fistulectomy involving complete excision of the fistula tract, allowing the wound to heal by secondary intention.

Patients are evaluated during surgery and followed postoperatively at 24 hours, 48 hours, 1 week, 2 weeks, 4 weeks, 3 months, and 6 months. The primary goals are to assess fistula healing rates and postoperative pain levels. Secondary goals include evaluating operative time, intraoperative blood loss, wound healing duration, complication rates, time to return to daily activities, fecal continence (measured by the Wexner Continence Score), and quality of life.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

40

Phase

  • Not Applicable

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Adult patients aged 18 years and above.
  • Diagnosis of primary (non-recurrent) low perianal fistula (intersphincteric or low transsphincteric involving less than one-third of the external sphincter) confirmed by clinical examination.
  • Fistula tract anatomy confirmed by preoperative endoanal ultrasound (EAUS) and/or pelvic MRI.
  • Fit for surgery under spinal or general anesthesia.
  • Willing and able to provide written informed consent.

Exclusion Criteria:

  • Complex or high perianal fistulae (suprasphincteric, extrasphincteric, or involving more than one-third of the external sphincter).
  • Recurrent or previously operated perianal fistulae.
  • Crohn's disease or other inflammatory bowel disease-associated fistulae.
  • Active anorectal sepsis or undrained abscess at the time of enrollment.
  • Immunocompromised patients (e.g., HIV/AIDS, long-term systemic corticosteroid therapy, post-organ transplantation).
  • Pre-existing fecal incontinence (baseline Wexner Continence Score > 5).
  • Pregnant or breastfeeding females.
  • Known bleeding disorders or therapeutic anticoagulation that cannot be temporarily safely discontinued.
  • History of prior pelvic irradiation.
  • Inability or unwillingness to comply with the postoperative follow-up protocol.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Laser Fistulotomy (FiLaC)
Patients undergo Fistula-tract Laser Closure (FiLaC™) using a 1470 nm diode laser system. The internal opening is curetted and sutured closed with polyglycolic acid suture. Granulation tissue is debrided with a fistula brush, and a radially emitting laser probe is introduced through the external opening to deliver energy circumferentially (10-14 W) at a continuous withdrawal rate of 1 mm/s to obliterate the tract. The external opening is left open or loosely sutured for drainage.
Procedure: Fistula-tract Laser Closure (FiLaC)
Debridement of the fistula tract using a fistula brush followed by closure of the internal opening with 2/0 polyglycolic acid suture. Photothermal obliteration of the tract is achieved using a 1470 nm diode laser system with a 360-degree radial emitting fiber delivering energy circumferentially (10-14 W) during steady withdrawal at 1 mm/s.
Active Comparator: Open Fistulectomy
Patients undergo conventional open fistulectomy. The fistula tract is cannulated with a malleable probe, followed by complete surgical excision of the tract and its epithelialized lining using electrocautery and sharp dissection. The surgical wound is left open to heal by secondary intention, with wound edge marsupialization performed as needed to prevent premature skin bridging.
Procedure: Open Fistulectomy
Complete surgical excision of the fistulous tract from the external opening to the internal opening using sharp dissection and electrocautery over a probe guide. The resulting wound is left open to heal by secondary intention with wound edge marsupialization performed as necessary.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Fistula Healing Rate at 6 Months
Time Frame: 6 months postoperatively
Percentage of participants achieving complete clinical fistula healing, defined as complete epithelialization of the surgical site and external wound with total absence of discharge or purulent drainage on clinical examination, without the need for secondary surgical intervention.
6 months postoperatively

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Assiut University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

October 1, 2026

Primary Completion (Estimated)

October 1, 2027

Study Completion (Estimated)

November 1, 2027

Study Registration Dates

First Submitted

August 27, 2026

First Submitted That Met QC Criteria

August 27, 2026

First Posted (Actual)

September 1, 2026

Study Record Updates

Last Update Posted (Actual)

September 1, 2026

Last Update Submitted That Met QC Criteria

August 27, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • FiLaC vs Open Fistulectomy

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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