Pathology of angiodysplasia in Klippel-Trenaunay syndrome.

Klippel-Trenaunay syndrome is a congenital angiodysplasia consisting of the triad of angiomas, osteohypertrophy and venous varicosities. Visceral involvement is not uncommon and may cause life-threatening complications. Presented here is a detailed study of the pathology of angiodysplasia in Klippel-Trenaunay syndrome. Venous fibromuscular dysplasia is the most prominent and consistent vascular lesion other than the cavernous hemangioma which is not unique to this syndrome. Dysplastic veins may also have deformed, insufficient, or absent valves. No agenesis or atresia of the deep veins is found in this series of patients.