Most of the patients suffering from perianal abscess in clinical practice will ask the doctor to give injections and medication to reduce inflammation first, and few of them will immediately cut and drain the pus according to the doctor’s suggestion, not knowing that this is a waste of money and medication. The medication may be effective at that time, but the abscess will recur after stopping the medication for a period of time, and the pus will spread to other interstitial spaces because it cannot be discharged from the body, which will bring problems to the future eradication. A few days ago, I saw a patient on the night shift who had a 7×6 cm lump in the left posterior part of the anus with severe pain 3 months ago. Five days ago, the pain recurred again with a high fever of 38.9°C. The patient was admitted to the hospital in an emergency after the infusion of fluids was ineffective. During surgery, the lesion was found to be not only in the left sciatic rectal space, but also extended through the posterior rectal space to the right posteriorly to the point that a mass also appeared on the right posterior rectal wall, making surgery more difficult. If he then cut open to drain the pus and decompress it, the pain will then be relieved, and even if time does not allow, he can elective reoperative treatment, because his pus has an outlet and has not had time to develop to the depths, and a simple anal fistula is formed after the incision, and later a fistulotomy can be performed again. Perianal abscess is a purulent disease of the perianal space. The disease is mainly characterized by rapid onset, perianal pain, swelling and nodules. When the abscess is superficial, the local redness, swelling, heat and pain are obvious, and the systemic symptoms are light; when the abscess is deeper and hidden, the systemic symptoms are mainly high fever, feeling of swelling in the rectum, and poor urination and defecation. Generally, purulent infection takes 7 days from the onset to pus formation, and if antibiotics are applied, it will delay the purulent days. The fatty tissue gap around the anus is more dull to pain, and the symptoms of deep abscess are not obvious in the early stage of the onset of anal symptoms, and when there are symptoms, the lesion has already spread to the surrounding area, and some patients who have the disease are bent on injections and medication, which will slow down the speed of abscess swelling, but cannot make the inflammatory mass dissipate and absorb, just like pressing an empty water gourd into the water, and when the hand is lifted, it naturally floats up, which cannot solve the problem and finally leaves a The hard nodes are not eliminated for a long time, and the primary infection foci of perianal abscess are not eradicated, and once the body’s resistance decreases, the hard nodes will be swollen and painful. In fact, the simple incision and drainage incision is in the perianal area, there is no incision in the anus, and the pain is not so heavy during and after the operation, and the pus flows when the anal fistula is formed after the incision, which is not a big obstacle to daily life. In medical terms, an anal fistula with an external opening is better than an infected site without an external opening, and the chances of successful surgery are greater, with less pain and faster recovery.