Butson Christopher R, Cooper Scott E, Henderson Jaimie M, McIntyre Cameron C
Department of Biomedical Engineering, Cleveland Clinic Foundation, Cleveland, OH, USA.
Med Image Comput Comput Assist Interv. 2006;9(Pt 2):429-37. doi: 10.1007/11866763_53.
Deep brain stimulation (DBS) is an established therapy for the treatment of movement disorders, and has shown promising results for the treatment of a wide range of other neurological disorders. However, little is known about the mechanism of action of DBS or the volume of brain tissue affected by stimulation. We have developed methods that use anatomical and diffusion tensor MRI (DTI) data to predict the volume of tissue activated (VTA) during DBS. We co-register the imaging data with detailed finite element models of the brain and stimulating electrode to enable anatomically and electrically accurate predictions of the spread of stimulation. One critical component of the model is the DTI tensor field that is used to represent the 3-dimensionally anisotropic and inhomogeneous tissue conductivity. With this system we are able to fuse structural and functional information to study a relevant clinical problem: DBS of the subthalamic nucleus for the treatment of Parkinsons disease (PD). Our results show that inclusion of the tensor field in our model caused significant differences in the size and shape of the VTA when compared to a homogeneous, isotropic tissue volume. The magnitude of these differences was proportional to the stimulation voltage. Our model predictions are validated by comparing spread of predicted activation to observed effects of oculomotor nerve stimulation in a PD patient. In turn, the 3D tissue electrical properties of the brain play an important role in regulating the spread of neural activation generated by DBS.
深部脑刺激（DBS）是一种用于治疗运动障碍的既定疗法，并且已在治疗多种其他神经系统疾病方面显示出有前景的结果。然而，对于DBS的作用机制或受刺激影响的脑组织体积知之甚少。我们已经开发出利用解剖学和扩散张量磁共振成像（DTI）数据来预测DBS期间激活组织体积（VTA）的方法。我们将成像数据与大脑和刺激电极的详细有限元模型进行配准，以实现对刺激传播的解剖学和电学精确预测。该模型的一个关键组成部分是DTI张量场，它用于表示三维各向异性和不均匀的组织电导率。借助这个系统，我们能够融合结构和功能信息来研究一个相关的临床问题：用于治疗帕金森病（PD）的丘脑底核DBS。我们的结果表明，与均匀、各向同性的组织体积相比，在我们的模型中纳入张量场会导致VTA的大小和形状出现显著差异。这些差异的程度与刺激电压成正比。通过将预测激活的传播与一名PD患者动眼神经刺激的观察效果进行比较，验证了我们的模型预测。反过来，大脑的三维组织电学特性在调节由DBS产生的神经激活传播中起着重要作用。
