Maks C B, Butson C R, Walter B L, Vitek J L, McIntyre C C
Department of Biomedical Engineering, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
J Neurol Neurosurg Psychiatry. 2009 Jun;80(6):659-66. doi: 10.1136/jnnp.2007.126219. Epub 2008 Apr 10.
Despite the clinical success of deep brain stimulation (DBS) for the treatment of Parkinson's disease (PD), little is known about the electrical spread of the stimulation. The primary goal of this study was to integrate neuroimaging, neurophysiology and neurostimulation data sets from 10 patients with PD, unilaterally implanted with subthalamic nucleus (STN) DBS electrodes, to identify the theoretical volume of tissue activated (VTA) by clinically defined therapeutic stimulation parameters.
Each patient specific model was created with a series of five steps: (1) definition of the neurosurgical stereotactic coordinate system within the context of preoperative imaging data; (2) entry of intraoperative microelectrode recording locations from neurophysiologically defined thalamic, subthalamic and substantia nigra neurons into the context of the imaging data; (3) fitting a three dimensional brain atlas to the neuroanatomy and neurophysiology of the patient; (4) positioning the DBS electrode in the documented stereotactic location, verified by postoperative imaging data; and (5) calculation of the VTA using a diffusion tensor based finite element neurostimulation model.
The patient specific models show that therapeutic benefit was achieved with direct stimulation of a wide range of anatomical structures in the subthalamic region. Interestingly, of the five patients exhibiting a greater than 40% improvement in their Unified PD Rating Scale (UPDRS), all but one had the majority of their VTA outside the atlas defined borders of the STN. Furthermore, of the five patients with less than 40% UPDRS improvement, all but one had the majority of their VTA inside the STN.
Our results are consistent with previous studies suggesting that therapeutic benefit is associated with electrode contacts near the dorsal border of the STN, and provide quantitative estimates of the electrical spread of the stimulation in a clinically relevant context.
尽管深部脑刺激（DBS）在治疗帕金森病（PD）方面取得了临床成功，但对于刺激的电扩散情况却知之甚少。本研究的主要目标是整合10例单侧植入丘脑底核（STN）DBS电极的PD患者的神经影像学、神经生理学和神经刺激数据集，以确定临床定义的治疗刺激参数所激活的理论组织体积（VTA）。
通过一系列五个步骤创建每个患者的特定模型：（1）在术前成像数据的背景下定义神经外科立体定向坐标系；（2）将神经生理学定义的丘脑、丘脑底核和黑质神经元的术中微电极记录位置输入成像数据背景中；（3）将三维脑图谱拟合到患者的神经解剖学和神经生理学；（4）将DBS电极定位在记录的立体定向位置，通过术后成像数据进行验证；（5）使用基于扩散张量的有限元神经刺激模型计算VTA。
患者特定模型显示，通过直接刺激丘脑底核区域的广泛解剖结构可实现治疗效果。有趣的是，在统一帕金森病评定量表（UPDRS）改善超过40%的5例患者中，除1例之外，其余患者的大部分VTA都在图谱定义的STN边界之外。此外，在UPDRS改善小于40%的5例患者中，除1例之外，其余患者的大部分VTA都在STN内。
我们的结果与先前的研究一致，表明治疗效果与STN背侧边界附近的电极触点有关，并在临床相关背景下提供了刺激电扩散的定量估计。
