Internal hemorrhoid is a soft vein group formed by the expanded varicose and hyperemia of the vein cluster under the mucous membrane at the end of the rectum above the dentate line of the anus [1]. The main symptoms are bleeding, prolapse, mucus soiling and itching [2]. The disharmonious movement and dysfunction of the pelvic floor exacerbate patients' defecation, thereby intensifying the symptoms of hemorrhoids [3]. According to Goligher 's classification [4], internal hemorrhoids with different degrees of prolapse can be divided into 4 degrees, and the treatment is also different accordingly. With the great progress of clinical techniques and development of minimally invasive treatment, more and more endoscopists have begun to use endoscopy for minimally invasive treatment of internal hemorrhoids. Preliminary clinical studies show that endoscopic minimally invasive treatment has the advantages of flexible operation, less pain, shorter recovery phase, less complication and less cost for patients [5], [6]. Among them, injection sclerotherapy (IS) is the main treatment for I-Ⅲ degree hemorrhoids with bleeding [7], by resulting in aseptic inflammatory reaction, and leads to secondary tissue fibrosis and reduction of hemorrhoid blood flow [8]. Endoscopic rubber band ligation (ERBL) is the main treatment for II-Ⅲ degree hemorrhoids with prolapse [9] by blocking the blood supply of the hemorrhoid mucosa, resulting in ischemia necrosis, ulceration and then fibrosis, which can lift up the anal cushion and effectively relieve prolapse symptoms [10].

Recent studies have shown that ERBL and IS performed simultaneously has a better effect on alleviating symptoms and signs of grades Ⅱ and Ⅲ internal hemorrhoids with prolapse and bleeding, and the incidence of postoperative bleeding, anal swelling and urinary retention is lower than that of ERBL alone [11]. However, we found in clinical practice that there is still a certain proportion of postoperative pain, and local injection of lidocaine during operation can relieve postoperative pain. To verify the effectiveness of this technique, we retrospectively studied 66 patients with internal hemorrhoids treated by ERBL combined with IS in the Department of Gastroenterology, Shenzhen Hospital of Southern Medical University, and compared the analgesic effect of lidocaine on postoperative pain.