gms | German Medical Science

55. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e. V. (DGNC)
1. Joint Meeting mit der Ungarischen Gesellschaft für Neurochirurgie

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

25. bis 28.04.2004, Köln

Article

Send article

Analysis of different influences on the intra-operative neurophysiological monitoring of Brodman Area 4 using compound muscle action potentials

Analyse verschiedener Einflussfaktoren auf das intraoperative neurophysiologische Monitoring der Brodman Area 4 mit Hilfe von evozierten Muskelaktionspotentialen

Meeting Abstract

Search Medline for

  • corresponding author Olaf Süss - Neurochirurgische Klinik, Charite-Universitätsmedizin Berlin, Campus Benjamin Franklin (CBF), Berlin
  • M. Brock - Neurochirurgische Klinik, Charite-Universitätsmedizin Berlin, Campus Benjamin Franklin (CBF), Berlin
  • T. Kombos - Neurochirurgische Klinik, Charite-Universitätsmedizin Berlin, Campus Benjamin Franklin (CBF), Berlin

Deutsche Gesellschaft für Neurochirurgie. Ungarische Gesellschaft für Neurochirurgie. 55. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC), 1. Joint Meeting mit der Ungarischen Gesellschaft für Neurochirurgie. Köln, 25.-28.04.2004. Düsseldorf, Köln: German Medical Science; 2004. DocDI.02.04

The electronic version of this article is the complete one and can be found online at: http://www.egms.de/en/meetings/dgnc2004/04dgnc0158.shtml

Published: April 23, 2004

© 2004 Süss et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.

Outline

Text

Objective

Brain tumor surgery is limited by the risk of postoperative neurological deficits. Intraoperative neurophysiological examination techniques, which are based on the electrical excitability of the human brain cortex, are thus still indispensable for surgery in eloquent areas such as the primary motor cortex (Brodman Area 4).

Methods

This study examined the data obtained from a total of 106 cerebral interventions for lesions with direct contact to and another 115 immediately adjacent to Brodman Area 4 in order to search for direct connections between intraoperative potential changes and specific surgical maneuvers or other non-surgical influences when using monopolar cortex stimulation (MCS) for continuous intraoperative neurophysiological monitoring.

Results

Compound muscle action potentials (CMAPs) were recorded from the thenar muscles and forearm flexors in accordance with the large representational area of the hand and forearm in Brodman Area 4. Statistical analysis of the parameters: latency, potential width and amplitude showed spontaneous latency prolongations or abrupt amplitude reductions as a reliable warning signal for direct involvement of the motor cortex or motor pathways. Various potential changes and their direct correlation to particular surgical techniques and different non-surgical reasons were found.

Conclusions

Like other intraoperative neurophysiological examination techniques, MCS has technical, anatomical and neurophysiological limitations. MCS must be considered a stimulation technique that enables reliable qualitative analysis of the recorded potentials and may thus be regarded as directly predictive. Nevertheless, a variety of surgical and non-surgical influences can cause positive or false negative results.