Fistulotomy is a common surgical procedure used to treat an anal fistula, an abnormal channel that develops near the anus. This technique is a definitive approach to curing this often painful and recurring condition. The main objective is to open the entire fistula tract, allowing it to drain and heal completely from the base outwards. This surgery is typically reserved for simple or low-lying fistulas that do not involve a significant portion of the anal sphincter muscles. By transforming the tunnel into an open groove, the surgeon ensures the eradication of the infection and promotes lasting resolution.
Understanding the Anal Fistula
An anal fistula is a small, abnormal tunnel connecting the anal canal (the final segment of the large intestine) to the skin near the anus. The vast majority of anal fistulas begin with an anal abscess, a painful collection of pus caused by an acute infection in one of the small glands lining the anal canal.
When an anal abscess spontaneously ruptures or is surgically drained, a persistent tunnel may remain, leading to a chronic fistula. The tract acts as a conduit for infected material to pass from the intestine to the skin, preventing the area from healing naturally.
Common symptoms include throbbing pain and swelling around the anus, often worsening when sitting or during bowel movements. Patients frequently experience a persistent discharge of pus or bloody fluid from the external opening, which can lead to chronic skin irritation.
Because the fistula tract rarely closes on its own, surgical intervention is necessary to prevent recurrent abscesses and chronic drainage. The goal of treatment is to eliminate the tract while preserving the function of the anal sphincter muscles, which control continence. Fistulotomy is often the preferred method for simple tracts due to its high success rate.
How a Fistulotomy is Performed
Fistulotomy is generally performed in an operating room as an outpatient surgery, allowing the patient to go home the same day. The patient receives anesthesia (general, spinal, or local with sedation) to ensure comfort. The surgeon first identifies the internal and external openings of the fistula, often using a specialized probe passed through the tract.
Once the tunnel is mapped, the surgeon performs the fistulotomy by “laying open” the tract. This involves making an incision along the entire length of the fistula, converting the closed, infected tunnel into an open, shallow wound.
The surgeon then meticulously cleans out the infected tissue lining the tract, a process known as curettage, to remove debris that could hinder healing. The sides of the incision may be stitched to the edges of the tract to create a flat, open wound, a technique called marsupialization.
The wound is intentionally left open to heal from the bottom up, preventing the skin from closing before the deeper tissue heals. This method ensures no pockets of infection remain and minimizes recurrence. The surgical time for a simple fistulotomy is typically less than an hour.
Recovery and Expected Outcomes
Preparation involves specific pre-operative instructions, such as fasting and arranging transportation home, as anesthesia prohibits driving. Some surgeons may also recommend an enema or laxative to clear the lower bowel before the operation.
Immediately following the procedure, pain and discomfort are managed with prescribed oral medication. Post-operative care centers on wound management, including frequent warm sitz baths. Soaking the anal area for 10 to 20 minutes several times a day helps keep the area clean, soothe the wound, and promote healing.
Patients should consume a high-fiber diet and use stool softeners to prevent straining during bowel movements. Some bloody or purulent drainage from the open wound is normal for several weeks, requiring a small gauze pad to absorb the discharge. While patients often return to daily routines within one to two weeks, complete healing can take four weeks to a few months, depending on the fistula’s size.
Fistulotomy boasts a high success rate, often exceeding 90% for simple anal fistulas, with a low risk of recurrence. The procedure is effective because it removes the entire infected tract, allowing tissue to regenerate cleanly. Preserving the function of the anal sphincter remains a primary focus, minimizing the risk of damage that could lead to continence issues in low-lying tracts.