Hemorrhoids are one of the most common anal diseases and can develop at any age. The pathogenesis of hemorrhoids is not completely clear at this time, but it is generally believed to be associated with a variety of causes such as prolonged sitting, constipation, pregnancy, chronic alcohol consumption, consumption of large amounts of irritating foods, perianal infections, and malnutrition. Modern surgical science believes that hemorrhoids originate from the normal anal cushion, which is an important structure used to assist in anal control functions and to distinguish the nature of the discharge. Hemorrhoids are divided into internal, external and mixed hemorrhoids. The most common symptoms of internal hemorrhoids are bleeding and prolapse, painless intermittent post-poo blood; while external hemorrhoids are mainly anal discomfort, occasional pain or itching; mixed hemorrhoids are internal and external hemorrhoids occurring simultaneously. The mixed hemorrhoids aggravated by a ring-shaped prolapse outside the anus are called annular hemorrhoids; the prolapsed hemorrhoids are embedded by the spastic anal sphincter to the point of edema and necrosis causing severe pain, called embedded hemorrhoids or strangulated hemorrhoids. The diagnosis of hemorrhoids mainly relies on anorectal examination, observation of the perianal situation and anal finger examination are the routine means of examination; in order to exclude rectal diseases, anoscopy and colonoscopy are also the routine methods of examination. The treatment of hemorrhoids should follow three principles: 1, asymptomatic hemorrhoids do not need treatment; 2, symptomatic hemorrhoids focus on reducing and eliminating symptoms, rather than the root cause; 3, hemorrhoids are mainly conservative treatment. The main conservative treatment includes improving dietary habits, increasing dietary fiber intake; improving bowel habits, avoiding forceful and prolonged defecation; hot water baths, using lubrication or suppositories in the anal canal, etc. Surgical treatment is mainly for more severe hemorrhoids, and there are many treatment options available: collar ligation treatment, internal hemorrhoid injection treatment, external hemorrhoid peeling and internal hemorrhoid ligation, and anastomotic suprahemorrhoidal mucosal circumcision. For patients who have undergone surgical treatment, post-operative treatments such as softening and laxative, swelling and pain relief are routinely required. As for the prognosis of hemorrhoids, which often recur, improving one’s poor lifestyle habits is the most effective measure to reduce the recurrence of hemorrhoids. Perianal abscesses and fistulas Perianal abscesses generally originate from infection of a tiny gland (anal gland) inside the anus. Some intestinal infections, such as inflammatory bowel disease, can also lead to them. When a perianal abscess is drained (spontaneously or therapeutically), it forms a duct from the gland to the perianal skin, known as an anal fistula. The presence of an anal fistula leads to continued oozing or pus flow from the perianal skin opening, and if the skin opening heals, an abscess can form again. Symptoms include persistent pain unrelated to bowel movements, with or without various discomforts such as swelling, perianal drainage and overflow, and fever. A perianal abscess or fistula must be treated surgically. Although a seemingly simple fistula can be treated simply, surgical treatment by a specialized colorectal surgeon is recommended due to its potential complications such as recurrence and incontinence. A variety of fistula procedures can be selectively applied to all types of fistulas, including fistulotomy, fistulotomy, LIFT, BIOLIFT, mucosal flap advancement, anatomic fistulotomy, and fistula ligature. Moderate to severe pain is most common in the first week postoperatively and can be treated with optional medication for analgesia. To return home after surgery, it is important to adhere to three to four sitz baths per day, and medications can be used to keep the bowels open. Take care to take good measures to prevent contamination of clothing with exudate. Defecation does not affect the healing of the wound. If healing is complete, there is usually no recurrence. It should be noted that the most important guarantee of a good prognosis is to follow the treatment advice of a specialist. Anal fissures are injuries to the anus and anal canal. Most of the causes are: 1) dry, bulky stools passing through the anal canal; 2) prolonged constipation and violent bowel movements; 3) chronic diarrhea; 4) inflammation in the recto-anal region (inflammatory bowel diseases such as Crohn’s disease); 5) childbirth. Other common causes can be anal canal tumors, HIV, syphilis, herpes virus infection or tuberculosis. Occasionally, some patients have anal fissures due to medical factors (e.g. rectal thermometry, enema tube, colonoscopy or ultrasound probe insertion into the anus). The typical clinical presentation of anal fissures is severe pain and a small amount of bleeding during defecation. Sometimes the pain can be re-induced by contraction spasms of the circumflex muscles (anal sphincter) around the anus. Patients with anal fissures are often reluctant to defecate for fear of pain, which leads to constipation and even fecal impaction; however, constipation causes drier and larger feces and aggravates anal fissures, forming a vicious circle. Through detailed history taking and gentle anal examination, the diagnosis of anal fissure can be clarified. Most fissures can be cured within a few weeks by: maintaining soft stools with dietary therapy (dietary fiber and fruits); relaxing the anal muscles with warm sitz baths several times a day (10-20 minutes, preferably after defecation) to promote healing; lubricating the anorectal area with paraffin oil; and using some special pessary or ointment. However, if symptoms persist after the above observed treatments, surgical intervention should be sought. Surgical treatment often involves cutting off a small portion of the internal anal sphincter to reduce its spasm and pain to promote fissure healing (internal anal sphincterotomy). Surgery may be performed under sacrococcygeal or epidural anesthesia.