gms | German Medical Science

63rd Annual Meeting of the German Society of Neurosurgery (DGNC)
Joint Meeting with the Japanese Neurosurgical Society (JNS)

German Society of Neurosurgery (DGNC)

13 - 16 June 2012, Leipzig

Predictive value and safety of intraoperative neurophysiological monitoring using motor evoked potentials in glioma surgery

Meeting Abstract

  • S.M. Krieg - Department of Neurosurgery, Technische Universität München, Munich, Germany
  • E. Shiban - Department of Neurosurgery, Technische Universität München, Munich, Germany
  • D. Droese - Department of Anesthesiology, Technische Universität München, Munich, Germany
  • J. Gempt - Department of Neurosurgery, Technische Universität München, Munich, Germany
  • N. Buchmann - Department of Neurosurgery, Technische Universität München, Munich, Germany
  • B. Meyer - Department of Neurosurgery, Technische Universität München, Munich, Germany
  • F. Ringel - Department of Neurosurgery, Technische Universität München, Munich, Germany

Deutsche Gesellschaft für Neurochirurgie. Japanische Gesellschaft für Neurochirurgie. 63. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Japanischen Gesellschaft für Neurochirurgie (JNS). Leipzig, 13.-16.06.2012. Düsseldorf: German Medical Science GMS Publishing House; 2012. DocFR.02.01

DOI: 10.3205/12dgnc177, URN: urn:nbn:de:0183-12dgnc1776

Published: June 4, 2012

© 2012 Krieg et al.
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Outline

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Objective: Resection of gliomas in or adjacent to the corticospinal tract (CST) or the rolandic region is widely performed using intraoperative neuromonitoring (IOM). Despite the fact that data on the safety of IOM is available, the significance and predictive value of the procedure is still under discussion. Moreover, cases of false negative monitoring affect the surgeon’s confidence in IOM. Therefore, we especially focused on cases of false negative IOM to reveal structural explanations.

Methods: Between 2007 and 2010 we resected 115 consecutive supratentorial gliomas in or close to eloquent motor areas using direct cortical stimulation for monitoring of motor evoked potentials (MEPs). Postoperatively, the monitoring data were reviewed and related to new postoperative motor deficit and postoperative imaging. Clinical outcomes were assessed during follow-up.

Results: MEP monitoring was successful in 112 cases (97.4%). Postoperatively, 30.3% of patients had a new motor deficit, which remained permanent in 12.5%. Progression-free follow-up was 9.7 months (range: 2 weeks–40.6 months). In 65.2% of all cases, MEPs were stable throughout the operation, but 8.9% of these showed a new temporary motor deficit, whereas 4.5% (5 patients) even presented with permanently deteriorated motor function representing false negative monitoring at first glance. However, all of these cases were caused by secondary hemorrhage, ischemia or resection of the supplementary motor area.

Conclusions: Continuous MEP monitoring provides reliable monitoring of the motor system, influences the course of operation in some cases, and has to be regarded as the standard for IOM of the motor system. In our series, we found no false negative MEP results.