Abstract: Objective To observe the effect of segmental dissection and preservation of skin flaps on severe mixed hemorrhoids.Methods A total of 72 patients with mixed hemorrhoids of grade Ⅲ and Ⅳ were randomly divided into experimental group and control group, with 36 cases in each group.The experimental group received segmental dissection and preservation of skin flaps, while the control group received traditional external dissection and internal ligation.The operation time, intraoperative bleeding volume, postoperative pain, local edema, healing time, and surgical satisfaction of the two groups were recorded.Results The effective rates of both groups were 100%, without statistical difference.There were 4 cases of anal stenosis in the control group and no anal stenosis case in the experimental group, with statistical difference.The experimental group showed less intraoperative bleeding volume, lower VAS pain score, lower local edema score, shorter wound healing time, higher satisfaction, and longer operation time than the control group, with statistical differences.Conclusion The clinical effect of segmental dissection and preservation of skin flaps on severe mixed hemorrhoids deserves popularizing.

Key words: Severe mixed hemorrhoids, Segmental dissection and preservation of skin flaps, External dissection and internal ligation, Clinical observation