Zheng Zhe, Li Yongjie, Li Jianyu, Zhang Yuqing, Zhang Xiaohua, Zhuang Ping
Beijing Institute of Functional Neurosurgery, Xuanwu Hospital, Beijing, China.
Stereotact Funct Neurosurg. 2010;88(1):29-34. doi: 10.1159/000260077. Epub 2009 Nov 20.
Deep brain stimulation of the subthalamic nucleus (STN-DBS) is a very effective surgical procedure for Parkinson's disease. It significantly improves cardinal parkinsonian symptoms as well as levodopa-induced dyskinesia. Interestingly, STN-DBS can also provoke or exacerbate dyskinesia. In the present study, stimulation-induced dyskinesia (SID) was found in the early stage (less than 1 month) after STN-DBS in some patients. The aim was to discuss this interesting phenomenon.
Side effects of each electrode contact were tested at 9.0 +/- 3.8 days (range, 3-16 days) after STN-DBS, and 40 contacts of 16 electrodes (15 patients) were found to induce dyskinesia. The location of these contacts was calculated in the postoperative magnetic resonance imaging, and was compared to the positions of active contacts and dorsal margin of the subthalamic nucleus (STN).
Most SID at the threshold manifested as repetitively dystonic involuntary movement, and the most common site was the contralateral lower limb (27/40, 67.5%). The mean location of the 40 contacts with SID was 11.9 +/- 0.9 mm lateral, 0.4 +/- 1.7 mm anterior, and 1.8 +/- 1.9 mm inferior to the midcommissural point. The point was located inferior to the dorsal margin of the STN (p = 0.01, t tests), and no significant difference was found between this point and the location of active contacts (p > 0.05, t tests).
In the early stage after STN-DBS, dyskinesia is easily induced by high-frequency stimulation of the upper portion of the STN, which may predict the best site for chronic stimulation.
丘脑底核深部脑刺激术（STN-DBS）是治疗帕金森病的一种非常有效的外科手术。它能显著改善帕金森病的主要症状以及左旋多巴诱导的运动障碍。有趣的是，STN-DBS也可引发或加重运动障碍。在本研究中，部分患者在STN-DBS术后早期（不到1个月）出现了刺激诱导性运动障碍（SID）。目的是探讨这一有趣现象。
在STN-DBS术后9.0±3.8天（范围3 - 16天）测试每个电极触点的副作用，发现16个电极（15例患者）的40个触点可诱发运动障碍。在术后磁共振成像中计算这些触点的位置，并与有效触点及丘脑底核（STN）背侧边缘的位置进行比较。
阈值下的大多数SID表现为反复性肌张力障碍性不自主运动，最常见部位是对侧下肢（27/40，67.5%）。40个有SID的触点的平均位置在联合中点外侧11.9±0.9 mm、前方0.4±1.7 mm、下方1.8±1.9 mm处。该点位于STN背侧边缘下方（p = 0.01，t检验），与有效触点位置之间未发现显著差异（p > 0.05，t检验）。
在STN-DBS术后早期，STN上部的高频刺激容易诱发运动障碍，这可能预示着慢性刺激的最佳部位。
