Sala F, Lanteri P, Bricolo A
Department of Neurological Sciences and Vision, Section of Neurosurgery, University of Verona.
Adv Tech Stand Neurosurg. 2004;29:133-69. doi: 10.1007/978-3-7091-0558-0_4.
Intraoperative Neurophysiology (ION) has established itself as one of the means by which modern neurosurgery can improve surgical results while minimizing morbidity. The advent of motor evoked potential (MEP) monitoring represents a landmark in this recent progress. ION consists of monitoring (the continuous "on-line" assessment of the functional integrity of neural pathways) and mapping (the functional identification and preservation of anatomically ambiguous nervous tissue) techniques. In this chapter we have attempted to critically review the evolution of MEP use during monitoring and mapping techniques for neurosurgical procedures in the brainstem and the spinal cord, providing the neurophysiological theoretical background and practical aspects of clinical applications. According to the experience from our and other groups involved in ION, we suggest the following: 1) ION is mandatory whenever neurological complications are expected as predicted by a known pathophysiological mechanism. It is therefore advisable to perform ION when dealing with brain stem and intramedullary spinal cord lesions. 2) MEP monitoring after transcranial electrical stimulation is today a feasible and reliable technique for use under general anesthesia. MEP monitoring is the most appropriate technique to assess the functional integrity of descending motor pathways in the brainstem and, foremost, in the spinal cord. 3) Mapping of the corticospinal tract at the level of the cerebral peduncle as well as mapping of the VII, IX-X and XII cranial nerve motor nuclei on the floor of the fourth ventricle is of great value with which to identify "safe entry zones" into the brainstem. 4) Other techniques, although safe and feasible, still lack rigorous validation in terms of prognostic value and correlation with the postoperative neurological outcome. These techniques include mapping of the corticospinal tract within the spinal cord and monitoring of the corticobulbar tracts. These techniques, however, are expected to open new perspectives in the near future.
术中神经生理学（ION）已成为现代神经外科手术提高手术效果并将发病率降至最低的手段之一。运动诱发电位（MEP）监测的出现是这一最新进展中的一个里程碑。ION包括监测（对神经通路功能完整性的连续“在线”评估）和定位（对解剖结构不明确的神经组织进行功能识别和保留）技术。在本章中，我们试图批判性地回顾MEP在脑干和脊髓神经外科手术监测和定位技术中的应用演变，提供神经生理学理论背景和临床应用的实际情况。根据我们和其他从事ION研究的团队的经验，我们提出以下建议：1）只要根据已知的病理生理机制预测到可能出现神经并发症，ION就是必不可少的。因此，在处理脑干和脊髓髓内病变时，建议进行ION。2）经颅电刺激后的MEP监测是一种在全身麻醉下可行且可靠的技术。MEP监测是评估脑干尤其是脊髓下行运动通路功能完整性的最合适技术。3）在大脑脚水平对皮质脊髓束进行定位以及在第四脑室底部对Ⅶ、Ⅸ - Ⅹ和Ⅻ颅神经运动核进行定位，对于确定进入脑干的“安全进入区”具有重要价值。4）其他技术虽然安全可行，但在预后价值以及与术后神经功能结果的相关性方面仍缺乏严格验证。这些技术包括脊髓内皮质脊髓束的定位和皮质延髓束的监测。然而，预计这些技术在不久的将来会开辟新的前景。
