Open Fistulectomy vs. Laser Closure for Low Perianal Fistula

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.

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.