There are 3 main types of rectal prolapse:part of the wall of the rectum (including all 3 wall layers) drop through the anus-this is called full-thickness rectal prolapse; the lining of the rectum drops through the anus-this is known as mucosal prolapse; the rectum collapses in on itself but doesn't fall through the anus-this is called occult or internal intussusception rectal prolapse.
Attribution: BUPA