Congenital arteriovenous malformations of the face. Report of a case.

Arteriovenous malformations (AVM) are uncommon vascular abnormalities which can be either developmental defects present from birth, or acquired ones, secondary to trauma. They may cause local swelling and discomfort, and also may present a potential for severe bleeding. Traumatic AVM are usually single fistulous channels, whereas congenital lesions are most often multiple interconnections of vessels of varying caliber that result in a diffuseness which renders clini-al delineation and treatment difficult. The nature of the lesion is determined by the stage of development of the vascular system during which it develops. Congenital lesions range from finely channelled capillary hemangiomas to large-bore, high-flow A-V fistulas. Most lesions are not observed at birth, but become manifest later in life; minor trauma and endocrine change are implicated as the stimuli for the initiation of hemodynamic activity. The diagnosis is clinical, with confirmation by arteriography. The treatment has not been completely satisfactory in all cases. Surgical intervention has been used most often, but newer techniques include cryotherapy and muscle embolization.