Stimulation selectivity in transcranial motor evoked potentials for monitoring during surgery for supratentorial lesions

IF 2 Q3 NEUROSCIENCES

Clinical Neurophysiology Practice Pub Date : 2026-01-01 Epub Date: 2026-01-30 DOI:10.1016/j.cnp.2026.01.006

Tammam Abboud , Jan-Bernd Wemhoff , Fares Komboz , Angelina Nazarenus , Tatiana Chacon , Dorothee Mielke , Veit Rohde

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引用次数: 0

Abstract

Objective

To identify the most selective electrode configuration for monitoring of transcranial motor evoked potentials (TcMEP) during supratentorial tumor surgery and determine the stimulation threshold at which bilateral corticospinal tract (CST) activation occurs at deeper white matter levels.

Methods

Fifty-six patients undergoing resection of supratentorial tumors without preoperative motor deficits were prospectively included. TcMEPs were elicited under general anesthesia using three electrode configurations: C1 ↔ C2, C3 ↔ C4, and C3/4 → Cz. Motor thresholds (MT) were recorded bilaterally from the abductor pollicis brevis (APB), and the selectivity ratio (ipsilateral/contralateral MT) was calculated. Electrode combinations were compared using paired t-tests. Linear regression assessed the influence of age, sex, height, and weight.

Results

The C3/4 → Cz montage demonstrated the highest selectivity ratio (median 248%, range: 140–364%), significantly greater than C1 ↔ C2 and C3 ↔ C4 (p < 0.001). Bilateral CST activation with C3/4 → Cz began at 140% of the contralateral MT. Age correlated with lower MTs; sex, height, and weight had no significant effect.

Conclusions

C3/4 → Cz is the most selective configuration for eliciting contralateral TcMEP and requires higher stimulation intensity before activating bilateral CST fibers at deeper levels.

Significance

This study supports using C3/4 → Cz to optimize TcMEP selectivity and reduce the risk of false-negative monitoring due to deep white matter stimulation.

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幕上病变手术中监测经颅运动诱发电位的刺激选择性

目的确定幕上肿瘤手术中经颅运动诱发电位（TcMEP）监测的最选择性电极配置，并确定双侧皮质脊髓束（CST）在更深白质水平激活的刺激阈值。方法前瞻性分析56例术前无运动障碍的幕上肿瘤切除术患者。tcmep在全身麻醉下用三种电极配置引起：C1↔C2， C3↔C4和C3/4→Cz。记录双侧短拇外展肌（APB）的运动阈值（MT），并计算选择性比（同侧/对侧MT）。电极组合采用配对t检验进行比较。线性回归评估了年龄、性别、身高和体重的影响。结果C3/4→Cz蒙太奇表现出最高的选择比（中位数248%，范围：140-364%），显著高于C1↔C2和C3↔C4 （p < 0.001）。C3/4→Cz的双侧CST激活始于对侧MT的140%。年龄与较低的MT相关；性别、身高和体重没有显著影响。结论sc3 /4→Cz是激发对侧TcMEP最具选择性的配置，在激活双侧CST纤维之前需要较高的刺激强度。意义本研究支持C3/4→Cz优化TcMEP选择性，降低深部白质刺激导致的假阴性监测风险。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Clinical Neurophysiology Practice NEUROSCIENCES-

CiteScore

3.90

自引率

0.00%

发文量

审稿时长

71 days

期刊介绍： Clinical Neurophysiology Practice (CNP) is a new Open Access journal that focuses on clinical practice issues in clinical neurophysiology including relevant new research, case reports or clinical series, normal values and didactic reviews. It is an official journal of the International Federation of Clinical Neurophysiology and complements Clinical Neurophysiology which focuses on innovative research in the specialty. It has a role in supporting established clinical practice, and an educational role for trainees, technicians and practitioners.