Brain arteriovenous malformations

INTRODUCTION

Arteriovenous malformations (AVMs) are the most dangerous congenital vascular malformations. They have become the focus of scientific study leading to technological advances that have permitted these high-flow lesions to be treated, often with a multidisciplinary approach utilizing surgical, endovascular, and radiosurgical techniques.

This topic review will discuss brain AVMs. Three other general subtypes of congenital vascular malformations have been described: developmental venous anomalies, capillary telangiectasias, and cavernous malformations. These are discussed separately. (See "Vascular malformations of the central nervous system".)

EPIDEMIOLOGY, PATHOGENESIS, AND PATHOLOGY

Brain AVMs occur in about 0.1 percent of the population, one-tenth the incidence of intracranial aneurysms. Supratentorial lesions account for 90 percent of brain AVMs; the remainder are in the posterior fossa. Brain AVMs account for 1 to 2 percent of all strokes, 3 percent of strokes in young adults, and 9 percent of subarachnoid hemorrhages [1].

Brain AVMs are considered sporadic congenital developmental vascular lesions, but their pathogenesis is not well understood. Rare cases of familial brain AVMs have been reported but it is unclear if these are coincidental or indicate true familial occurrence [2]. However, genetic variation may influence brain AVM development and clinical course [3,4].

There is a higher prevalence of vascular malformations associated with hereditary hemorrhagic telangiectasia (HHT; Osler-Weber-Rendu syndrome). Patients with HHT may have cerebral or spinal cord involvement with telangiectasias, brain AVMs, aneurysms, or cavernous malformations. (See "Hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu syndrome)".)