小脳脳動静脈奇形におけるガンマナイフ治療の長期成績解析

抄録

Gamma knife radiosurgery (GK) is a standard treatment for AVMs, but it tends to be avoided for cerebellar arteriovenous malformation (C-AVM) because of concerns about fatal posterior fossa hemorrhage before nidus obliteration. The goal of this study was to evaluate the long-term outcomes of GK for C-AVM. Sixty patients treated with GK between 1990 and 2015 were included in the study. The median age, volume, maximal diameter, and prescription dose were 42 years, 1.4 ml, 19 mm, and 20 Gy, respectively. Forty patients (67%) developed hemorrhage prior to GK. The cumulative obliteration rates were 49% and 79% at 3 and 5 years, respectively. A prescription dose of ＞ 20 Gy was associated with better obliteration via multivariate analysis. The 15-year significant neurological event (SNE)-free rate was 96%. The annual post-GK hemorrhage rates were 1.5% and 0.3% before and after obliteration, respectively. In conclusion, GK is a favorable alternative for C-AVMs, providing a high obliteration rate and very low risk of SNEs. The treatment strategy for C-AVM should be determined after considering the merits and drawbacks of surgery and GK.