"How to Diagnose Anal Fistula in Detail?"

Anal fistula, known as "hanging carbuncle" in traditional Chinese medicine, is usually a granulomatous tract around the anus formed by the rupture of perianal abscess and long-term non-healing. Anal fistula can be diagnosed through methods such as the methylene blue test, internal opening examination, and probe examination. Here are the methods for checking anal fistula:

1. Methylene Blue Test: Insert a moderately sized gauze into the anus, then inject a 5% methylene blue aqueous solution into the fistula from the external opening. Gently pull out the gauze and observe the location of the internal opening.

2. Internal Opening Examination: Insert an anoscope into the anus. The internal opening of the anal crypts can be seen as red, swollen, and inflamed, and the internal opening is mostly located here. Repeated examination of the anal crypts with an anal crypt hook can make it easy to find the internal opening.

3. Probe Examination: Insert a probe into the fistula from the external opening and insert the index finger into the anal canal. Most probes can pass through the internal opening at the dentate line. For curved fistulas, the probe may not pass smoothly. Avoid using excessive force to prevent the probe from puncturing the fistula wall and causing new infections.

After the above explanation, we have learned about the examination methods for anal fistula. The next step is to treat it. Surgery is the best method for treating anal fistula.