丘脑腹外侧核定向毁损术中电生理定位的定量研究

A quantitative study of localization using electrophysiological technique during stereotaxic thalamotomy

目的了解帕金森病丘脑腹外侧核定向毁损手术中低频电刺激电压值与靶点中心至内囊距离的定量关系。方法18例施行丘脑腹外侧核定向毁损手术疗效满意的帕金森病患者进行手术后MR检查,测量毁损灶至内囊距离。以手术中低频电刺激电压(V)值作为应变量,靶点中心至内囊距离(L)为自变量,应用SPSS统计软件进行回归分析。结果靶点中心至内囊距离为4.6～12.0mm,平均7.32mm;刺激电压为1.2～5.0V,平均2.87V;V值与L值之间存在直线回归关系,具有显著性意义(P=0.000)。结论在施行丘脑腹外侧核定向毁损手术中,当运动性电刺激电压<0.6V,毁损灶至内囊距离<4.6mm时,手术安全性较低;若电压>4.0V,毁损灶至内囊距离>12mm时,电极至内囊距离过远,手术效果欠佳。

Objective To study the quantitative relationship between the distance from lesioned point in ventral lateral nucleus (VLN) to internal capsule and the parameter of motor stimulation during thalamotomy in Parkinsonian disease. Methods Eighteen parkinsonian patients who had been successfully treated in CT guided stereotactic localization were enrolled in this study. The distance from the target point to internal capsule was measured directly on postoperative MRI. Let the value L- the distance from the target point to internal capsule as independent value, and V- low frequency stimulation voltage in operation as dependent value, then regressional analysis was performed by using the statistical software SPSS. Results The distances from the target point to internal capsule were 4.6-12.0 mm (averaged 7.32 mm), stimulation voltages were 1.2-5.0 V (averaged 2.87 V). There was linearity regression between L and V with significance (P = 0.000). Conclusion The operational safety is rather low when the motor electric stimulation voltage less than 0.6 V, and the distance from the target point to internal capsule less than 4.6 mm in stereotaxic thalamotomy. The poor operational effect will be resulted if the motor electric stimulation > 4.0 V and the distance from the target point to internal capsule > 12 mm. It is important that further studies on large scale with a great number of patients should be performed in order to verify this conclusion and avoiding any bias since this report is only based on limited cases.