The first three primary diseases that caused ROOC were intra-mucosal intussusception of the rectum (11 cases,33.33% ),rectocele(10 cases,30.3%),and descent of perineum(5 cases,15.15%).

• 原发病出现率排在前三位的分别是直肠黏膜脱垂伴套叠11例(33.；33%25)；直肠前突10例(30