Supplementary Material for: Induction of Bradykinesia with Pallidal Deep Brain Stimulation in Patients with Cranial-Cervical Dystonia

<i>Background:</i> Deep brain stimulation (DBS) of the globus pallidus internus (GPi) is an effective and well-tolerated treatment for idiopathic generalized dystonia. More recently, it has been applied as a treatment for focal and segmental dystonias. This patient population offers an opportunity to study the effects of alteration of pallidal outflow on previously normal limb function. <i>Methods:</i> We sought to retrospectively characterize the extent of novel GPi DBS-induced adverse motor effects in patients with adult-onset cervical and cranial-cervical dystonia using a questionnaire, and compared the findings to dystonia improvement as measured by standard scales. <i>Results:</i> Despite significant improvement in dystonia (65% in mean Burke-Fahn-MarsdenDystonia Rating Scale motor score, p &lt; 0.005, and 59% in mean Toronto Western Spasmodic Torticollis Rating Scale score, p &lt; 0.008), slowing and difficulty with normal motor function was reported in previously nondystonic extremities in 10 of 11 patients. Symptoms were common in both upper and lower extremities and included new difficulties with handwriting (82%), getting up from a chair or in/out of a car (73%), and walking (45%), and were not associated with aberrant lead placement near the internal capsule. <i>Conclusion:</i> Although GPi DBS was shown to be effective in these patients, the influence of GPi DBS on nondystonic body regions deserves further investigation.

背景：苍白球内侧部（globus pallidus internus, GPi）脑深部电刺激术（deep brain stimulation, DBS）是治疗特发性全身性肌张力障碍的疗效确切且耐受性良好的手段。近年来，该技术已被应用于局灶性及节段性肌张力障碍的治疗。该患者队列可为研究苍白球传出通路改变对原本正常肢体功能的影响提供契机。
方法：本研究通过问卷形式，对成年起病的颈型及颈颅型肌张力障碍患者接受苍白球内侧部脑深部电刺激术后出现的新型运动不良反应程度进行回顾性分析，并将该结果与通过标准化量表评估得到的肌张力障碍改善情况进行对比。
结果：尽管患者肌张力障碍获得显著改善（伯克-法恩-马斯登肌张力障碍评定量表（Burke-Fahn-Marsden Dystonia Rating Scale）运动评分平均下降65%，p<0.005；多伦多西部痉挛性斜颈评定量表（Toronto Western Spasmodic Torticollis Rating Scale）评分平均下降59%，p<0.008），但11例患者中有10例报告其原本无肌张力障碍的肢体出现运动减慢及正常运动功能执行困难。该症状在上肢及下肢均较为常见，具体表现为新发书写困难（82%）、起身或上下车困难（73%）以及行走障碍（45%），且与电极植入内囊附近位置异常无关联。
结论：尽管本研究证实苍白球内侧部脑深部电刺激术对该类患者疗效确切，但苍白球内侧部脑深部电刺激术对非肌张力障碍受累身体区域的影响仍需进一步研究。