An anal fistula is a tunnel-like abnormality that runs from an abscessed area in the anal canal to an opening in the skin near the anus. Anal fistulas usually form because an anal gland has developed an infection that causes an abnormal tunnel to form between the colon and the anal canal running under the skin and out through a hole in the skin near the anus. There are many solutions to do this treatment, laser is a good choice.
The conical probe is a special probe, containing a bare fiber within a special conical glass tip is used. The special glass tip provides wide illumination of laser light, ensuring a gentle application of energy, while having a sharp distal end for easy tissue penetration.
This laser probe is very flexible and it is threaded into the fistula tract and then withdrawn as laser energy is being emitted. While the conical laser probe is being pulled back slowly the tract is being closed. This eliminates the need for a surgeon to try to tediously extract the unwanted fistula tissue during a long complex surgery. The laser treatment takes only a few minutes and provides the possibility to completely spare the enucleation of the fistula out of the healthy tissue.
A paper shows two different groups using different wavelengths to do this treatment. For the first 8 patients they used a laser with a wavelength of 980 nm which required 13 watts power to seal the tract. For the rest of the patients, they used a laser with a wavelength of 1470 nm with 10 watts power. Although no major complication was reported in their study, 8 patients treated with the 980 nm wavelength laser experienced postoperative pain and anismus. They postulated that the use of higher wave length laser with lower power (10 watts) settings can provide better post-operative results compared to 980 nm laser with 13 watts power.