What is an anal fistula? An anal fistula is short for anorectal fistula, also called hemorrhoid fistula or fistula in Chinese medicine. Why is it called a fistula? This is because its main symptom is the repeated outflow of pus or pus and blood from the sores on the skin around the anus, and even the flow of feces, like a broken house that often leaks, so our ancestors named it a fistula. When it comes to fistulas, it is important to distinguish them from sinus tracts, which have an internal opening in the anal canal and an external opening outside the anal canal, and are connected by interconnecting tubes that leak secretions and pus from inside the anus to the outside. A sinus is a blind canal with only one outward sore opening; it also has secretions and pus, but it has no internal opening and is not connected to the internal anal canal. There is a big difference between the former tube called fistula and the latter tube called sinus. The main symptom of fistula is the constant flow of pus and fecal water from the sore, just like a rat stealing feces hidden inside the sore, and from time to time harming people stealing feces, so the image of anal fistula is called fecal rat. The fistula is called “Fistula” in Western medicine, which is derived from the Latin word meaning reed, water pipe or shawl. Sinus”, which means lake bay or crypt, is named according to its form. The fistula is a common disease in anorectology, which can occur in both men and women, but mostly in young adults. It is not clear why women have fewer anal fistulas. However, it is thought that perhaps it is because men have larger and deeper anal fossa than women, which makes it easier for bacteria to invade, or because men’s anal sphincter is strong and powerful, and the pressure in the rectum becomes greater, making it easier to press bacteria into the anal fossa. Is surgery the only cure for anal fistula? From the point of view of medical research, anal fistula is caused by the invasion of bacteria into the anal fossa, but there is still no recognized method to prevent the invasion of bacteria into the anal fossa, therefore, at this stage, it is not possible to prevent anal fistula very effectively. Of course, some conventional measures such as keeping the bowels open, avoiding spicy and irritating foods, avoiding alcohol and getting enough sleep can also have some preventive effect. The actual fact is that you can find a lot of people who are not able to get a good deal on a lot of things. The only way to cure an anal fistula is through surgery. You should abandon the psychological state of being shy or afraid of pain and seek out an anorectal specialist as soon as possible to remove the fistula from the fossa to the fistula. As the severity of fistula varies, so does the surgical approach. The surgical approach must be tailored to the specific case of the fistula. However, there is a pattern to the course of the fistula, with most fistulas with an external opening within 5 cm of the anal verge having an internal opening inside the corresponding anus, and slightly more complex fistulas with the primary focus almost directly behind, the most common of which is the horseshoe fistula. The initial fistula is still unbranched and not only can the surgery be easily completed, but the function of the anus can be quickly restored to normal. A simple low anal fistula can be treated painlessly without hospitalization under local anesthesia, but the surgery requires removal of the entire fistula and scar tissue containing the anal fossa in order to prevent recurrence, so complete healing time is longer, usually about a month. If the fistula is left untreated, some lesions may move to the perirectal area and between the sphincter muscles, and the fistula may spread deeply and widely. It is best to be hospitalized for this level of fistula because the treatment of the wound after surgery is also very important and is one of the reasons for the high recurrence rate of fistulas. When the fistula penetrates above the full length of the external anal sphincter, surgery by incision and dilation is considered to be the best and safest method, requiring a certain level of experience and skill. The surgery should be performed to minimize the damage to the anal sphincter to protect the anal sphincter function as much as possible and to avoid the sequelae of anal incontinence.