If you've been told you have an anal fistula, you're likely worried about two things: Will I need a colostomy bag? and Will surgery make me incontinent? The answer to both, with modern laser surgery, is almost certainly no.
But understanding exactly what a fistula is — and why it behaves differently from piles or fissures — is essential to choosing the right treatment and surgeon.
What Exactly Is an Anal Fistula?
An anal fistula is an abnormal tunnel (tract) that connects the inside of the anal canal to the skin near the anus. Think of it like an underground passage — one opening inside the bowel (the internal opening) and another on the skin outside (the external opening).
The tract is lined with infected tissue and granulation. Because of this lining, a fistula cannot heal on its own or with medicines. The tract must be destroyed or removed surgically.
What Causes a Fistula?
In 90% of cases, the sequence is:
- Blocked anal gland — one of the tiny glands just inside the anus gets clogged
- Abscess forms — bacteria multiply inside the blocked gland, creating a painful, pus-filled cavity
- Abscess drains — either surgically or on its own (it bursts through the skin)
- Fistula forms — in about 50% of abscess cases, the drainage path doesn't close. It remains as a permanent infected tunnel.
Less common causes include Crohn's disease, tuberculosis (more common in India), and previous anal surgery.
Symptoms of an Anal Fistula
The hallmark symptoms are:
- Persistent discharge of pus, blood, or mucus from a small hole near the anus (this is the defining feature)
- Intermittent pain and swelling near the anus — which flares up when the external opening blocks and pus builds up, then subsides when it drains again
- Skin irritation and itching around the external opening from constant discharge
- History of a previous perianal abscess
- Recurring abscesses in the same area (a strong indicator of an underlying fistula)
Types of Fistulas (This Determines Your Surgery)
Fistulas are classified by their relationship to the anal sphincter muscle:
- Intersphincteric (most common, ~45%): The tract runs between the internal and external sphincter muscles. Simplest to treat.
- Transphincteric (~30%): The tract passes through the external sphincter. Requires sphincter-preserving techniques.
- Suprasphincteric (~20%): A high, complex tract. Challenging surgery.
- Extrasphincteric (~5%): Rare. Often associated with Crohn's or previous surgery.
Modern Laser Treatment: VAAFT and FiLaC
Traditional open fistulotomy (cutting the tract open) works well for simple fistulas but carries a significant risk of incontinence for complex ones — because it involves cutting through sphincter muscle.
VAAFT (Video-Assisted Anal Fistula Treatment) inserts a tiny camera into the fistula tract. The surgeon can see the entire tract on screen, identify all branches, clean out infected tissue, and then destroy the internal opening with laser energy — all without cutting any sphincter muscle.
FiLaC (Fistula-tract Laser Closure) uses a radial laser probe to deliver energy along the entire fistula wall, causing it to shrink and seal shut from the inside. Again, zero sphincter muscle is cut.
Recovery After Laser Fistula Surgery
- Day 1: Discharge from hospital. Mild discomfort manageable with oral painkillers.
- Day 3–5: Return to desk work.
- Week 1–2: Regular wound care and follow-up with surgeon.
- Week 4–6: Full recovery. The internal tract fibroses (heals solid).
Recurrence rates with VAAFT/FiLaC are under 10% for most fistula types — compared to 25–30% with open surgery for complex cases. And critically, the risk of incontinence is near zero.
When to See a Doctor
See a specialist immediately if you have:
- Persistent discharge from a hole near (but not inside) the anus
- Recurring perianal abscesses (2 or more in the same area)
- A fistula that was treated but has recurred
SURGISAATHI connects you with VAAFT/FiLaC-trained colorectal surgeons in Mumbai and Chandigarh. Your consultation is 100% free, private, and available via WhatsApp.