Evoked Responses and Electromyography in Intraoperative Monitoring in Neurosurgery

Authors: S. Ostrý;  L. Stejskal
Authors‘ workplace: Neurochirurgická klinika 1. LF UK, IPVZ a ÚVN Praha
Published in: Cesk Slov Neurol N 2010; 73/106(1): 8-19
Category: Minimonography


The requirement that perioperative morbidity decrease in neurosurgery becomes ever more pressing. A possible contribution may be made by intraoperative monitoring of conduction in important tracts during general anaesthesia. The techniques of central sulcus identification (somatosensory evoked potential, SEP phase reversal) and motor strip location by cortical stimulation are well developed. Intraoperative motor tract monitoring is advisable in the performance of resection of intramedullary tumours. Monitoring of ascendant tracts and cranial nerves is an integral part of high‑risk surgery in the cerebellopontine angle and in the brain stem. The techniques used for stimulation and recording, as well as the ways in which responses and changes are evaluated, differ from common electromyographical practice. Close teamwork among the prime movers in the operating theatre – the neurosurgeon, the anaesthesiologist and the neurophysiologist – is vital to worthwhile and reliable monitoring.

Key words:
evoked potentials – electromyography – intraoperative monitoring – general anaesthesia


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