Course of headaches associated with cAVMs after radiosurgery

The purpose of this study is to evaluate the response of headaches associat ed with cerebral arteriovenous malformations following radiosurgery and det ermine the factors that are associated with a positive outcome. From our series of 700 patients whose cAVM was treated by radiosurgery, thi s study includes 109 patients (48 males, 61 females) with a mean age of 32 when radiosurgery was performed. Headaches resolved in 37 patients (53.7%), decreased in 14 patients (20.3%), persisted in 16 patients (23.2%), and ev en increased in frequency in 2 (2.9%). Headaches disappeared 2 years follow ing radiosurgery in the majority of patients (31 out of 37: 83.3%). The dis appearance rate of headaches was better when it was the only sign of the ma lformation (64%) or preceded an epileptic seizure (60%) with respect to the case when it preceded cerebral hemorrhage (34.8%). Headaches having the best response were those with 1 to 2 episodes per mont h (64.9%) and whose episode duration runs less than 3 hours (67.6%) Unilate ral headaches accounted for 86.5% of resolved headaches whereas bilateral h eadaches were only 8.1% and even less were the diffuse ones (5.4%). The bes t evolution was obtained for those associated with a parietal location of t he cerebral arteriovenous malformation, followed by rolandic (respectively 55.5% and 50%). Occipital malformation was associated with headache disappe arance in 38.1% and temporal with 34.3%, whereas frontal location was assoc iated with headache disappearance in only 25% of the cases. Headache disappearance was often correlated with cerebral arteriovenous mal formation outcome after radiosurgery (64.9% of disappearance in case of com plete obliteration). However, in 24.8%, headaches disappeared prior to the malformation obliteration and were associated with a decrease of the flow o f the nidus volume or with the nidus disappearance with the persistence of a precocious venous drainage. Headaches disappeared in spite of the malform ation persistence in 5.4% of the cases. We found de novo headaches in one p atient one year following RS. Another patient presented an episode of heada che 12 hours following RS. The course of headaches associated with cerebral arteriovenous malformation s after radiosurgery is positive in the majority of cases and correlated to the malformation outcome. This correlation suggests a link between cerebra l arteriovenous malformations and headaches and the equal benefit of radios urgery on both of them.