Department of Neurosurgery, Göttingen University Medical Center, Göttingen, Germany.
Department of Neurology, Göttingen University Medical Center, Göttingen, Germany.
PLoS One. 2020 Nov 6;15(11):e0241752. doi: 10.1371/journal.pone.0241752. eCollection 2020.
Intraoperative microelectrode recording (MER) and test-stimulation are regarded as the gold standard for proper placement of subthalamic (STN) deep brain stimulation (DBS) electrodes in Parkinson's disease (PD), requiring the patient to be awake during the procedure. In accordance with good clinical practice, most attending neurologists will request the clinically most efficacious trajectory for definite lead placement. However, the necessity of microelectrode-test-stimulation is disputed, as it may limit the access to DBS therapy, excluding those not willing or incapable of undergoing awake surgery.
We retrospectively analyzed the MERs and microelectrode-test-stimulation results with regard to the decision on definite lead placement and clinical outcome in a cohort of 67 PD-patients with STN-DBS. All patients received bilateral quadripolar ring electrodes. To ascertain overall procedural efficacy, we calculated the surgical index (SI) by comparing preoperative motor improvement induced by levodopa to that induced by stimulation 7 to 18 months after surgery, measured as the relative difference between ON and OFF-states on the Unified Parkinson's Disease Rating Scale motor part (UPDRS-3). Additionally, a side-specific surgical index (SSSI) was calculated using the unilateral assessable items of the UPDRS-3. The SSSI where microelectrode-test-stimulation overruled MER were compared to those where the result of microelectrode-test-stimulation was congruent to MER results.
A total of 134 electrodes were analyzed. For final lead placement, the central trajectory was chosen in 54% of patient hemispheres. The mean SI was 0.99 (± 0.24). SSSI averaged 1.04 (± 0.45). In 37 lead placements, microelectrode-test-stimulation overruled MER in the final trajectory selection, in 27 of these lead placements adverse effects during microelectrode-test-stimulation were decisive. Neither the number of test electrodes used nor the STN-signal length had an impact on the SSSI. The SSSI did not differ between lead placements with MER/microelectrode-test-stimulation congruency and those where the results of microelectrode-test-stimulation initiated lead placement in a trajectory with shorter STN signal.
Intraoperative testing is mandatory to ensure an optimal motor outcome of STN DBS in PD-patients when using quadripolar ring electrodes. However, we also demonstrated that neither the length of the STN-signal on MER nor the number of test electrodes influenced the motor outcome.
术中微电极记录（MER）和测试刺激被认为是正确放置丘脑底核（STN）深部脑刺激（DBS）电极的金标准，这要求患者在手术过程中保持清醒。根据良好的临床实践，大多数主治神经科医生会要求使用对临床最有效的轨迹来确定电极的位置。然而，微电极测试刺激的必要性存在争议，因为它可能限制 DBS 治疗的机会，排除那些不愿意或不能接受清醒手术的患者。
我们回顾性分析了 67 例接受 STN-DBS 的帕金森病（PD）患者的 MER 和微电极测试刺激结果，以确定最终电极位置，并评估其与临床结果的关系。所有患者均接受双侧四极环电极。为了确定总体手术效果，我们通过比较术前左旋多巴诱导的运动改善与术后 7-18 个月刺激诱导的运动改善，计算手术指数（SI），这是通过统一帕金森病评定量表运动部分（UPDRS-3）的 ON 和 OFF 状态之间的相对差异来衡量的。此外，我们还使用 UPDRS-3 的单侧可评估项目计算了单侧手术指数（SSSI）。比较微电极测试刺激结果与 MER 结果不一致时的 SSSI 与微电极测试刺激结果与 MER 结果一致时的 SSSI。
共分析了 134 个电极。在 54%的患者半球中，最终选择了中央轨迹。平均 SI 为 0.99（±0.24）。SSSI 平均为 1.04（±0.45）。在 37 个电极位置中，微电极测试刺激在最终轨迹选择中推翻了 MER，在这些电极位置中，微电极测试刺激过程中的不良反应起决定性作用。测试电极的数量和 STN 信号长度均未对 SSSI 产生影响。MER/微电极测试刺激结果一致和微电极测试刺激结果开始引导电极放置在 STN 信号较短的轨迹的电极位置之间，其 SSSI 无差异。
当使用四极环电极时，术中测试对于确保 PD 患者 STN-DBS 的最佳运动效果是必需的。然而，我们还证明，MER 上 STN 信号的长度和测试电极的数量都不会影响运动效果。
