Lars Leksell Center for Gamma Surgery, Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia, USA.
World Neurosurg. 2011 Jul-Aug;76(1-2):87-95; discussion 57-8. doi: 10.1016/j.wneu.2011.02.003.
To evaluate the long-term imaging and clinical outcomes of patients with brainstem arteriovenous malformations (AVMs) treated with Gamma Knife surgery (GKS).
The study included 85 patients with brainstem AVMs undergoing GKS during the period 1989-2007. The locations of the nidi were the midbrain in 42 patients, pons in 31 patients, and medulla oblongata in 12 patients. The volume of the nidi ranged from 0.1-8.9 mL (median 1.4 mL, mean 1.9 mL), and the prescription dose ranged from 5-32 Gy (median 20 Gy, mean 19.9 Gy). After the initial Gamma procedure, 18 patients had repeat GKS for AVM residuals that were still patent. Two patients had a third GKS 7 years and 16 years after a failed repeat GKS. Clinical follow-up ranged from 24-252 months with a mean of 100 months (median 102 months) after the initial GKS.
GKS yielded a total angiographic obliteration in 50 (58.8%) patients and subtotal obliteration in 4 (4.7%) patients. In 22 (25.9%) patients, the AVMs remained patent. In 9 patients (10.6%), no flow voids were observed on magnetic resonance imaging (MRI), but angiographic confirmation was unavailable. A small nidus volume and a high prescription dose were significantly associated with increased AVM obliteration rate. Radiation-induced changes developed in 34 patients (40%); 24 were asymptomatic, 1 patient had only headache, and 9 patients developed neurologic deficits. One patient developed a large cyst 6 years after GKS.
Given the poor surgical outcome of brainstem AVMs, the results of 59% nidus obliteration and 6% permanent neurologic deficits make GKS a reasonable management of these difficult lesions.
评估伽玛刀手术（GKS）治疗脑干动静脉畸形（AVM）患者的长期影像学和临床结果。
本研究纳入了 1989 年至 2007 年间接受 GKS 治疗的 85 例脑干 AVM 患者。病灶位于中脑 42 例，脑桥 31 例，延髓 12 例。病灶体积 0.1-8.9ml（中位数 1.4ml，均值 1.9ml），处方剂量 5-32Gy（中位数 20Gy，均值 19.9Gy）。初次 GKS 后，18 例仍有残留 AVM 未闭患者行重复 GKS。2 例患者在初次重复 GKS 失败 7 年和 16 年后行第三次 GKS。临床随访时间 24-252 个月，初次 GKS 后平均 100 个月（中位数 102 个月）。
GKS 使 50 例（58.8%）患者完全闭塞，4 例（4.7%）患者次全闭塞。22 例（25.9%）患者 AVM 仍未闭塞。9 例（10.6%）患者 MRI 未见流空，但无法行血管造影证实。小病灶体积和高处方剂量与 AVM 闭塞率增加显著相关。34 例（40%）患者出现放射性改变；24 例无症状，1 例仅头痛，9 例出现神经功能缺损。1 例患者 GKS 后 6 年出现大囊肿。
鉴于脑干 AVM 手术效果不佳，59%的病灶闭塞率和 6%的永久性神经功能缺损率使 GKS 成为这些病变的合理治疗方法。
