Krammer Matthias Johannes, Wolf Stefan, Schul David Baruch, Gerstner Werner, Lumenta Christianto Bernardo
Department of Neurosurgery, Academic Teaching Hospital Munich Bogenhausen, Technical University of Munich, Munich, Germany.
Br J Neurosurg. 2009 Feb;23(1):48-55. doi: 10.1080/02688690802563349.
Intraoperative motor evoked potential (MEP) monitoring in patients with spinal and cranial lesions is thought to be a valuable tool for prevention of postoperative motor deficits. Aim of this study was to investigate its diagnostic value in a spinal and a cranial patient group. Ninety-six patients, 31 with spinal and 65 with intracranial lesions, were studied. Transcranial stimulation was performed with a high-frequency electrical train stimulation using two subdermal needle electrodes. MEPs were recorded from the pathology-related muscles. Decreasing amplitudes of 50% or more, increasing stimulus intensities of 20% or more or increased latencies were taken as warning criteria. MEP recording was possible in 90% of the spinal and 98% of the cranial group. With two further exclusions, 28 patients of the spinal and 62 of the cranial group were analyzed. We saw a temporary maximum amplitude reduction of 50% or more and an increase in stimulation intensity of 20% or more in 8 spinal and 29 cranial patients. Five of the spinal and nine of the cranial patients deteriorated in motor function postoperatively. One patient with normal MEP monitoring showed a temporary motor weakness postoperatively. Latencies were normal in all patients. Given both warning criteria, intraoperative MEP changes had a sensitivity of 83%/ 100% and a specificity of 86%/ 62% (spinal/ cranial group). The positive predictive value of MEP changes for postoperative motor function deterioration was 63%/ 31%, and the negative predictive value was 95%/ 100%. Transcranial electrical monitoring of MEP is a practicable and safe method. However, there are many events, which can cause amplitude changes of MEP independent from surgical manipulations. Although sensitivity is high for both groups, this results in a moderate specificity for the cranial group and a low positive predictive value for both groups.
术中运动诱发电位（MEP）监测被认为是预防脊柱和颅脑病变患者术后运动功能障碍的一项重要手段。本研究旨在探讨其在脊柱和颅脑疾病患者群体中的诊断价值。对96例患者进行了研究，其中31例患有脊柱病变，65例患有颅内病变。使用两个皮下针电极进行高频电刺激串刺激来进行经颅刺激。从与病变相关的肌肉记录MEP。将波幅下降50%或更多、刺激强度增加20%或更多或潜伏期延长作为预警标准。在脊柱疾病组90%的患者和颅脑疾病组98%的患者中可以记录到MEP。再排除另外2例后，对脊柱疾病组的28例患者和颅脑疾病组的62例患者进行了分析。我们发现8例脊柱疾病患者和29例颅脑疾病患者出现了波幅暂时最大下降50%或更多以及刺激强度增加20%或更多的情况。脊柱疾病组5例患者和颅脑疾病组9例患者术后运动功能恶化。1例MEP监测正常的患者术后出现了暂时的运动无力。所有患者的潜伏期均正常。综合两项预警标准，术中MEP变化在脊柱疾病组/颅脑疾病组中的敏感性为83%/100%，特异性为86%/62%。MEP变化对术后运动功能恶化的阳性预测值为63%/31%，阴性预测值为95%/100%。经颅电刺激MEP监测是一种可行且安全的方法。然而，有许多事件可导致与手术操作无关的MEP波幅变化。尽管两组的敏感性都很高，但这导致颅脑疾病组的特异性中等，两组的阳性预测值都较低。
