Departments of1Neurological Surgery and.
2University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
J Neurosurg. 2018 Feb;128(2):617-626. doi: 10.3171/2016.11.JNS162044. Epub 2017 Apr 7.
OBJECTIVE Unilateral Gamma Knife thalamotomy (GKT) is a well-established treatment for patients with medically refractory tremor who are not eligible for invasive procedures due to increased risk of compications. The purpose of this study was to evaluate whether staged bilateral GKT provides benefit with acceptable risk to patients suffering from disabling medically refractory bilateral tremor. METHODS Eleven patients underwent staged bilateral GKT during a 17-year period (1999-2016). Eight patients had essential tremor (ET), 2 had Parkinson's disease (PD)-related tremor, and 1 had multiple-sclerosis (MS)-related tremor. For the first GKT, a median maximum dose of 140 Gy was delivered to the posterior-inferior region of the nucleus ventralis intermedius (VIM) through a single isocenter with 4-mm collimators. Patients who benefitted from unilateral GKT were eligible for a contralateral GKT 1-2 years later (median 22 months). For the second GKT, a median maximum dose of 130 Gy was delivered to the opposite VIM nucleus to a single 4-mm isocenter. The Fahn-Tolosa-Marin (FTM) clinical tremor rating scale was used to score tremor, drawing, and drinking before and after each GKT. The FTM writing score was assessed only for the dominant hand before and after the first GKT. The Karnofsky Performance Status (KPS) was used to assess quality of life and activities of daily living before and after the first and second GKT. RESULTS The median time to last follow-up after the first GKT was 35 months (range 11-70 months). All patients had improvement in at least 1 FTM score after the first GKT. Three patients (27.3%) had tremor arrest and complete restoration of function (noted via FTM tremor, writing, drawing, and drinking scores equaling zero). No patient had tremor recurrence or diminished tremor relief after the first GKT. One patient experienced new temporary neurological deficit (contralateral lower-extremity hemiparesis) from the first GKT. The median time to last follow-up after the second GKT was 12 months (range 2-70 months). Nine patients had improvement in at least 1 FTM score after the second GKT. Two patients had tremor arrest and complete restoration of function. No patient experienced tremor recurrence or diminished tremor relief after the second GKT. No patient experienced new neurological or radiological adverse effect from the second GKT. Statistically significant improvements were noted in the KPS score following the first and second GKT. CONCLUSIONS Staged bilateral GKT provided effective relief for medically refractory, disabling, bilateral tremor without increased risk of neurological complications. It is an appropriate strategy for carefully selected patients with medically refractory bilateral tremor who are not eligible for deep brain stimulation.
单侧伽玛刀丘脑切开术（GKT）是一种成熟的治疗方法，适用于因并发症风险增加而不适合进行有创手术的药物难治性震颤患者。本研究旨在评估分期双侧 GKT 是否能为患有致残性药物难治性双侧震颤的患者提供可接受风险的获益。
11 名患者在 17 年期间（1999-2016 年）接受了分期双侧 GKT。8 名患者患有原发性震颤（ET），2 名患者患有帕金森病（PD）相关震颤，1 名患者患有多发性硬化症（MS）相关震颤。对于第一次 GKT，通过 4mm 准直器在单一等中心点，将 140Gy 的最大剂量输送至腹后内侧核（VIM）的后下方。单侧 GKT 获益的患者有资格在 1-2 年后（中位数 22 个月）进行对侧 GKT。对于第二次 GKT，将 130Gy 的最大剂量通过单一 4mm 等中心点输送至对侧 VIM 核。采用 Fahn-Tolosa-Marin（FTM）临床震颤评分量表在每次 GKT 前后评估震颤、绘图和饮水情况。仅在第一次 GKT 前后评估优势手的 FTM 书写评分。Karnofsky 表现状态（KPS）用于评估第一次和第二次 GKT 前后的生活质量和日常生活活动能力。
第一次 GKT 后，中位随访时间为 35 个月（范围 11-70 个月）。所有患者在第一次 GKT 后至少有一项 FTM 评分得到改善。3 名患者（27.3%）震颤停止，功能完全恢复（FTM 震颤、书写、绘图和饮水评分均为零）。第一次 GKT 后，没有患者出现震颤复发或震颤缓解减弱。1 名患者因第一次 GKT 出现新的暂时神经功能缺损（对侧下肢偏瘫）。第二次 GKT 后，中位随访时间为 12 个月（范围 2-70 个月）。第二次 GKT 后，9 名患者至少有一项 FTM 评分得到改善。2 名患者震颤停止，功能完全恢复。第二次 GKT 后，没有患者出现震颤复发或震颤缓解减弱。第二次 GKT 后，没有患者出现新的神经或放射学不良事件。第一次和第二次 GKT 后，KPS 评分均有显著改善。
分期双侧 GKT 为药物难治性、致残性双侧震颤患者提供了有效缓解，且不会增加神经并发症风险。对于不适合深部脑刺激的药物难治性双侧震颤患者，这是一种合适的治疗策略。
