Arteriovenous malformations are abnormal collections of immature blood vessels within the brain which can cause induce or hemorrhage. The risk of lesion bleeding is 2 - 4% per year, the morbidity is 2 - 4 % per year and the mortality is 1% per year. Mortality and morbidity rates per bleed are 10 - 15% and 20 - 30%, respectively. AVMs can be treated with resection or radiosurgery depending upon the lesion's location and size. Prior to either therapy the option for embolization using glue, particles, metal coils and alcohol is available to reduce the size and vascularity of the lesion.

Occipital AVM before embolization (L) and after embolization.

Occiptal AVM before embolization (L) and after embolization (R).