St. Lukes University Health Network, Bethlehem, Pennsylvania.
NuVasive Clinical Services, Ann Arbor, Michigan.
Oper Neurosurg (Hagerstown). 2018 Jun 1;14(6):654-660. doi: 10.1093/ons/opx172.
Dorsal root ganglion stimulation is a neuromodulation therapy used for chronic neuropathic pain. Typically, patients are awakened intraoperatively to confirm adequate placement.
To determine whether neuromonitoring can confirm placement in an asleep patient.
This is a prospective analysis of 12 leads placed in 6 patients. Lead confirmation was confirmed by awake intraoperative testing, as well as asleep testing utilizing neuromonitoring. Patients were used as their own control. Sensory and motor thresholds for each patient with awake and asleep neuromonitoring testing were recorded. Intraoperative impedance and postoperative programming were also recorded.
In each patient, paresthesias were generated prior to motor contractions in the awake patient. For each patient, somatosensory evoked potential responses were present after lowering below the dropout threshold of electromyogram responses with neuromonitoring. There were varying degrees of separation in the thresholds that did not appear to be consistent across level or diagnosis. Smaller degrees of separation between thresholds during awake testing also held true in the asleep patient. This was further confirmed with postoperative programming. Impedances did not alter the separation in thresholds or amount of stimulation required for responses. One patient was combative during awake testing, and therefore motor thresholds were not obtained. This same patient was determined to have a ventral placement, confirmed with awake and asleep neuromonitoring testing.
This series demonstrates that the proposed neuromonitoring protocol can be used in an asleep patient to assure proper positioning of the dorsal root ganglion electrode in the dorsal foramen by generating somatosensory evoked potential responses in the absence of electromyogram responses.
背根神经节刺激是一种用于治疗慢性神经性疼痛的神经调节疗法。通常，患者在术中被唤醒以确认电极位置是否合适。
确定神经监测是否可以在睡着的患者中确认电极位置。
这是对 6 名患者的 12 个导联进行的前瞻性分析。通过术中唤醒测试以及利用神经监测进行的睡眠测试来确认导联的位置。患者自身作为对照。记录了每位患者在清醒和睡眠神经监测测试时的感觉和运动阈值。还记录了术中阻抗和术后程控。
在每位患者中，在清醒患者出现运动收缩之前产生了感觉异常。对于每位患者，在降低到肌电图反应的失活阈值以下后，利用神经监测出现了体感诱发电位反应。在阈值方面存在不同程度的分离，但这种分离似乎并不一致，无论是在水平上还是在诊断上。在清醒测试中，阈值之间的较小分离在睡眠患者中也存在。这一点在术后程控中也得到了进一步证实。阻抗并未改变阈值之间的分离程度或所需刺激量以产生反应。一位患者在清醒测试时表现出攻击性，因此未获得运动阈值。对这名患者进行了评估，认为其电极放置在腹侧，这一点通过清醒和睡眠神经监测测试得到了证实。
本系列研究表明，所提出的神经监测方案可用于睡眠患者，通过在没有肌电图反应的情况下产生体感诱发电位反应，从而确保背根神经节电极在背侧孔中的正确位置。
