Vascular ectasias of the colon.

Vascular ectasias are an acquired type of arteriovenous malformation distinct from neoplastic and congenital lesions. They can be the source of occult, recurrent or massive colonic bleeding usually in elderly patients but, occasionally, in younger adults. The vascular lesions are usually small but can be quite diffuse. The majority occurs in the right colon, but in our group of patients, a substantial number occurred distal to the hepatic flexure. The diagnosis can be made preoperatively, with colonoscopy but, more consistently, with arteriography. Therefore, arteriography should be performed in any patient with bleeding of the colon before surgical intervention. We recommend resection of the involved segment of the intestine as the treatment of choice.