Hemihypertrophy of the soft and bone tissue, hemangiomata, and varicose veins form the basic triad of this syndrome. Unilateral lesions of the legs with cutaneous and subcutaneous hemangiomas, varicosities, phlebectasis and occasional arteriovenous fistulae were emphasized in earlier reports, but later findings indicate involvement of many other parts of the body. Vascular anomalies may be present at birth or may appear in infancy. Occasional associated abnormalities may include lymphangiomatous anomalies, limb deformities, cutis marmorata, micro- or macrocephaly, eye diseases, and craniofacial deformities. Most patients have normal mentality, except when vascular lesions invade the cerebral tissue. In the absence of arteriovenous fistulae, the syndrome is often referred to as Weber syndrome or Parkes Weber syndrome. Klippel-Trenaunay-Weber syndrome is associated in some cases with Sturge-Weber angiomatosis.