Departments of Neurology, Neurosurgery, and Biomedical Engineering and Physics, University of Vienna, Austria.
Neuromodulation. 2003 Oct;6(4):248-53. doi: 10.1046/j.1525-1403.2003.03032.x.
The aim of this study was to investigate the causation of an insufficient clinical response to acute external stimulation after implantation of brain stimulating electrodes in patients with idiopathic Parkinson's disease (IPD). This study represents to our knowledge the first consecutive postoperative monitoring of the electrical properties of electrodes and tissue in this patient cohort. We hypothesized that changes in brain tissue resistance would be etiologic for this clinically observed phenomenon. Eight patients with IPD were monitored over a fixed time course (day 1-7). The voltage drop on the electrodes and in the tissue was measured. Our measurements indicate a significant inhomogeneity of the surrounding tissue and a marked interpatient difference of the electrode voltage drop. The changes of the voltage drop on the electrodes and the tissue were insignificant over the time course. We conclude that the decline of the clinical benefit is not due to an alteration of tissue resistivity. As an explanation, we postulate that the reactive formation/resolution of edema around the electrode has the same resistivity as the target and is therefore not detectable by our measurements or modulated by a still unknown mechanism.
本研究旨在探讨脑刺激电极植入后患者对外界刺激的急性反应不足的原因。据我们所知，这是首次在这一患者队列中对电极和组织的电性能进行连续术后监测。我们假设脑组织电阻的变化是这一临床观察现象的病因。8 名特发性帕金森病患者在固定时间内（第 1-7 天）进行监测。测量电极和组织上的电压降。我们的测量结果表明，周围组织存在明显的不均匀性，电极电压降的个体间差异也很大。电极和组织上的电压降随时间的变化不显著。我们得出结论，临床疗效的下降不是由于组织电阻率的改变。作为一种解释，我们假设电极周围水肿的反应性形成/消退与目标具有相同的电阻率，因此无法通过我们的测量检测到，或者被一个未知的机制所调节。
