Abstract
Twelve consecutive patients presenting with unexplained recurrent gastrointestinal bleeding were investigated by selective visceral angiography. A cause for the bleeding was shown in all 12 cases, and in eight the lesion responsible was diagnosed radiologically as an area of angiodysplasia. Abnormal areas were pinpointed by fluoroscopy and examination of the resected bowel with a dissecting microscope after injecting the vessels with barium. Histologically these areas had various microvascular abnormalities. Angiodysplasia is a useful descriptive radiological term, but does not seem to represent a single pathological entity.