An anal fistula is an abnormal, infected tunnel connecting a gland inside the anal canal to the skin around the anus. It usually follows a pus boil (perianal abscess) that burst or was drained.

No. Unlike piles or a new fissure, a fistula has an infected tract that doesn't heal with antibiotics or ointments. Closing the tract surgically or with a laser is the definitive treatment.

FiLaC is a sphincter-saving technique in which a flexible radial laser fibre is passed into the fistula tract. The laser energy destroys and seals the infected tract from the inside, without cutting the surrounding sphincter muscles.

Open fistulotomy or fistulectomy cuts through the sphincter muscles to lay open the tract. In high or complex fistulas this carries a real risk of leakage of gas or stool, and leaves large wounds that heal slowly.

The laser fibre is passed through the tract itself, without cutting the muscle fibres, so the internal and external sphincters are kept. This keeps the risk of leakage very low.

With careful tract mapping (and an MRI or ultrasound when needed), FiLaC by an experienced surgeon like Dr. Ranvijay Bharti has success rates of about 85–90%, without risking the sphincter muscle.