Walsh & Hoyt: Arteriovenous Malformations

Arteriovenous malformations (AVMs) are the most common form of intracranial vascular hamartoma. The prevalence in unselected populations is about 1 in 100,000 per year. AVMs occur slightly more often in men than in women, with a ratio of about 1.4:1. The majority of intracranial AVMs occur as an isolated, sporadic phenomenon; however, familial cases have been described. Since they are congenital, they can become symptomatic at any age including infancy and the elderly. In the majority of patients (70%), however, they do not produce symptoms until the 2nd or 3rd decade of life. They frequently present during puberty. The data on AVM hemorrhage during pregnancy are controversial and inconclusive and there is no evidence that cesarean section is better than vaginal delivery.