Bruno Sabine, Nikolov Petyo, Hartmann Christian J, Trenado Carlos, Slotty Philipp J, Vesper Jan, Schnitzler Alfons, Groiss Stefan J
Department of Neurology, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
Institute of Clinical Neuroscience and Medical Psychology, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
Neuromodulation. 2021 Feb;24(2):343-352. doi: 10.1111/ner.13234. Epub 2020 Jul 15.
Deep brain stimulation (DBS) of the posterior subthalamic area (PSA) and the ventral intermediate thalamic nucleus (VIM) is a well-established therapy for essential tremor (ET), but it is frequently associated with side effects like dysarthria or gait ataxia. Directional DBS (dDBS) may be a way to activate fiber tracts more selectively. Is dDBS for ET superior to omnidirectional DBS (oDBS) regarding therapeutic window and clinically as effective as oDBS?
Ten patients with ET treated with PSA/VIM-DBS were recruited. Therapeutic window served as primary outcome parameter; clinical efficacy, volume of neuronal activation, and total electrical energy delivered (TEED) served as secondary outcome parameters. Therapeutic window was calculated for all three dDBS directions and for oDBS by determining therapeutic thresholds and side effect thresholds. Clinical efficacy was assessed by comparing the effect of best dDBS and oDBS on tremor and ataxia rating scales, and accelerometry. Volume of neural activation and TEED were also calculated for both paradigms.
For best dDBS, therapeutic window was wider and therapeutic threshold was lower compared to oDBS. While side effect threshold did not differ, volume of neural activation was larger for dDBS. In terms of clinical efficacy, dDBS was as effective as oDBS.
dDBS for ET widens therapeutic window due to reduction of therapeutic threshold. Larger volume of neural activation for dDBS at side effect threshold supports the notion of persistent directionality even at higher intensities. dDBS may compensate for slightly misplaced leads and should be considered first line for PSA/VIM-DBS.
丘脑底后区（PSA）和丘脑腹中间核（VIM）的深部脑刺激（DBS）是治疗特发性震颤（ET）的成熟疗法，但它经常伴有构音障碍或步态共济失调等副作用。定向DBS（dDBS）可能是一种更有选择性地激活纤维束的方法。就治疗窗口而言，ET的dDBS是否优于全向DBS（oDBS），且在临床上与oDBS一样有效？
招募了10例接受PSA/VIM-DBS治疗的ET患者。治疗窗口作为主要结局参数；临床疗效、神经元激活体积和总传递电能（TEED）作为次要结局参数。通过确定治疗阈值和副作用阈值，计算所有三个dDBS方向和oDBS的治疗窗口。通过比较最佳dDBS和oDBS对震颤和共济失调评定量表以及加速度测量的影响来评估临床疗效。还计算了两种模式的神经激活体积和TEED。
与oDBS相比，最佳dDBS的治疗窗口更宽，治疗阈值更低。虽然副作用阈值没有差异，但dDBS的神经激活体积更大。在临床疗效方面，dDBS与oDBS一样有效。
ET的dDBS由于治疗阈值降低而拓宽了治疗窗口。在副作用阈值下dDBS的神经激活体积更大，支持了即使在更高强度下仍存在持续方向性的观点。dDBS可以弥补电极位置略有偏差的问题，应被视为PSA/VIM-DBS的一线治疗方法。
