Abnormal rectum morphology Hemorrhoids 2019-06-14T10:37:17Z Piles Enlarged, bulging blood vessels in and around the anus often associated with rectal bleeding, itching, and pain. Hemorrrhoids result from dilation of the submucosal vascular tissue in the distal anal canal. This vascular tissue is supported by connective tissue that, when weakened, leads to descent or prolapse of the hemorrhoids. Internal hemorrhoids originate above the dentate line (i.e., the junction between columnar and squamous epithelium) and are viscerally innervated and, therefore, painless. External hemorrhoids originate below the dentate line, have somatic innervation, and can cause pain. Some patients have both internal and external (mixed) hemorrhoids. Haemorrhoids