Surgical and radiosurgical results of the treatment of cerebral arteriovenous malformations

Abstract

Microsurgical resection of a cerebral arteriovenous malformation (AVM) allows for an immediate therapeutic cure. Stereotactic radiosurgery (SRS) is a reasonable alternative for inoperable or high-risk lesions requiring treatment. Few series evaluate overall results that include data from both modalities as they more often focus on their treatment method of choice. In this study, we evaluated our AVM database of 129 patients seen over the past eight years at our institution: 73 were treated with microsurgery (57%) while 37 (29%) were treated with SRS. We reviewed angiographic obliteration rates, complication rates, and outcome data, excluding seven patients treated with SRS as they did not have at least two years of angiographic follow-up. Patients undergoing microsurgery had smaller AVM (mean 2.2 cm compared to 3.5 cm for SRS), a smaller proportion of eloquent AVM (53% compared to 83% for SRS), a greater proportion of AVM with superficial drainage only (75% compared to 40% for SRS), and more grade 1 and 2 AVM (78% compared to 17% for SRS). The overall obliteration rate was 80%: 92% for microsurgery and 50% for SRS. The latter increased to 92% for AVM <3 cm, but the obliteration rate was 18% for those AVM >3 cm. Transient complications, including post-SRS hemorrhage, were seen in 11% of patients overall (8% after microsurgery, 17% after SRS). At follow-up, 53% of patients had improved, 37% remained the same, 7% had become worse and 3% had died. As a result of post-SRS hemorrhage, a greater proportion of patients was worse or had died after SRS (20%) compared to those who had been treated with microsurgery (5%).