• Toshinori Hasegawa, Takenori Kato, Takehiro Naito, Takafumi Tanei, Kou Okada, Risa Ito, Yuta Koketsu, and Kento Hirayama.
• Department of Neurosurgery, Gamma Knife Center, Komaki City Hospital, Komaki, Japan.
• Neurosurgery. 2022 Jun 1; 90 (6): 784-792.

BackgroundThe information about long-term risks of hemorrhage and late adverse radiation effects (AREs) after stereotactic radiosurgery for brain arteriovenous malformations (AVMs) is lacking.ObjectiveTo evaluate the long-term risks of hemorrhage and late ARE rates in patients with AVM treated with Gamma Knife surgery (GKS).MethodsWe examined 1249 patients with AVM treated with GKS. The Spetzler-Martin grade was I in 313 patients (25%), II in 394 (32%), III in 458 (37%), and IV/V in 84 (7%). The median treatment volume was 2.5 cm3, and the median marginal dose was 20 Gy.ResultsThe median follow-up period was 61 months. The 5- and 10-year nidus obliteration rates were 63% and 82%, respectively. The 5- and 10-year cumulative hemorrhage rates were 7% and 10%, respectively. The annual hemorrhage rate was 1.5% for the first 5 years post-GKS, which decreased to 0.5% thereafter. During the follow-up period, 42 symptomatic cyst formations/chronic encapsulated hematomas ([CFs/CEHs], 3%) and 3 radiation-induced tumors (0.2%) were observed. The 10- and 15-year cumulative CF/CEH rates were 3.7% and 9.4%, respectively.ConclusionGKS is associated with reduced hemorrhage risk and high nidus obliteration rates in patients with AVM. The incidence of late AREs tended to increase over time. The most common ARE was CF/CEH, which can be safely removed; however, careful attention should be paid to the long-term development of fatal radiation-induced tumors.Copyright © Congress of Neurological Surgeons 2022. All rights reserved.

27 keywords...

hide…