Departments of1Neurology.
2Neurosurgery, and.
J Neurosurg. 2024 Apr 5;141(3):730-741. doi: 10.3171/2024.1.JNS231867. Print 2024 Sep 1.
The objective of this study was to describe the quantitative features of intraoperative electromyographic recordings obtained from cranial nerve III, IV, and VI neuromonitoring using 25-mm intraorbital electrodes, in the larger context of demonstrating the practicality of this technique during neurosurgical cases.
A 25-mm-long shaft-insulated intraorbital needle electrode is routinely used at the authors' institution for extraocular muscle (EOM) electromyographic monitoring of the inferior rectus, superior oblique, and/or lateral rectus muscles when their function is at risk. Cases monitored between January 1, 2021, and December 31, 2022, were reviewed for patient demographics, tumor location and pathology, EOMs monitored, pre- and postoperative examination, and complications from electrode placement. Compound muscle action potentials on triggered electromyography, as well as neurotonic discharges on free-run electromyography, were described quantitatively.
There were 141 cases in 139 patients reviewed during the 24-month time span, with 278 EOMs monitored (inferior rectus/superior oblique/lateral rectus muscles 68/68/142). Triggered electromyography yielded biphasic or triphasic compound muscle action potentials from EOMs with a mean onset latency of 1.51 msec (range 0.94-3.22 msec), mean maximal peak-to-trough amplitude of 1073.93 μV (range 76.75-7796.29 μV), and high specificity for the channel in nearly all cases. Neurotonic discharges were recorded in 30 of the 278 EOMs (with all 3 muscles represented) and associated with a greater incidence of new or worsened ophthalmoparesis (OR 4.62, 95% CI 1.3-16.4). There were 2 cases of small periorbital ecchymosis attributed to needle placement; additionally, 1 case of needle-related intraorbital hematoma occurred after the review period.
The 25-mm shaft-insulated intraorbital electrode facilitates robust and consistent electromyographic recordings of EOMs that are advantageous over existing techniques. Combined with the relative ease of needle placement and low rate of complications, the technique is practical for neuromonitoring during craniotomies.
本研究旨在描述使用 25 毫米眶内电极获得的颅神经 III、IV 和 VI 术中肌电图记录的定量特征，同时展示该技术在神经外科手术中的实用性。
作者所在机构常规使用 25 毫米长轴绝缘眶内针电极，用于监测下直肌、上斜肌和/或外直肌的眼外肌肌电图，以监测其功能是否受到影响。对 2021 年 1 月 1 日至 2022 年 12 月 31 日期间监测的病例进行患者人口统计学、肿瘤位置和病理学、监测的眼外肌、术前和术后检查以及电极放置并发症的回顾性分析。描述触发肌电图的复合肌肉动作电位以及自由运行肌电图的神经紧张放电的定量特征。
在 24 个月的时间内，共对 139 名患者的 141 例病例进行了回顾性分析，监测了 278 条眼外肌（下直肌/上斜肌/外直肌 68/68/142）。触发肌电图从眼外肌产生双相或三相复合肌肉动作电位，平均起始潜伏期为 1.51 毫秒（范围 0.94-3.22 毫秒），平均最大峰峰值幅度为 1073.93 微伏（范围 76.75-7796.29 微伏），在几乎所有情况下对通道都具有高度特异性。30 条 278 条眼外肌（所有 3 条肌肉均有代表）记录到神经紧张放电，与新的或恶化的眼肌麻痹发生率增加相关（OR 4.62，95%CI 1.3-16.4）。有 2 例眶周小瘀斑归因于针的放置；此外，在审查期后，有 1 例与针相关的眶内血肿。
25 毫米轴绝缘眶内电极有利于对眼外肌进行强有力且一致的肌电图记录，优于现有技术。结合针放置相对容易和并发症发生率低的特点，该技术在开颅手术中的神经监测中具有实用性。
