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72. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC)
Joint Meeting mit der Polnischen Gesellschaft für Neurochirurgie

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

06.06. - 09.06.2021

The effect of different frequencies on motor evoked potentials in intraoperative neuromonitoring

Der Effekt unterschiedlicher Stimulationsfrequenzen auf motorisch evozierte Potentiale im Rahmen des intraoperativen Neuromonitorings

Meeting Abstract

  • presenting/speaker Maximilian Stein - Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Neurochirurgische Klinik und Poliklinik, Mainz, Deutschland
  • Malte Ottenhausen - Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Neurochirurgische Klinik und Poliklinik, Mainz, Deutschland
  • Nora Marinova - Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Neurochirurgische Klinik und Poliklinik, Mainz, Deutschland
  • Darius Kalasauskas - Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Neurochirurgische Klinik und Poliklinik, Mainz, Deutschland
  • Harald Krenzlin - Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Neurochirurgische Klinik und Poliklinik, Mainz, Deutschland
  • Naureen Keric - Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Neurochirurgische Klinik und Poliklinik, Mainz, Deutschland
  • Florian Ringel - Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Neurochirurgische Klinik und Poliklinik, Mainz, Deutschland

Deutsche Gesellschaft für Neurochirurgie. 72. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Polnischen Gesellschaft für Neurochirurgie. sine loco [digital], 06.-09.06.2021. Düsseldorf: German Medical Science GMS Publishing House; 2021. DocP201

doi: 10.3205/21dgnc482, urn:nbn:de:0183-21dgnc4828

Veröffentlicht: 4. Juni 2021

© 2021 Stein et al.
Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). Lizenz-Angaben siehe http://creativecommons.org/licenses/by/4.0/.


Gliederung

Text

Objective: Intraoperative electrical transcranial and cortical stimulation is used to reduce the risk of damaging the motor system during neurosurgical procedures. In order to quickly identify a decline in the measured potentials it is necessary to install a continuous intraoperative monitoring with high temporal resolution. Therefore, measurements could be done continuously with high frequency. The objective of this study was to investigate whether high frequency motor evoked potentials can lead to a build-up effect of the measured potentials falsely showing stable or even rising potentials and therefore leading to false prediction of the postoperative neurological outcome.

Methods: We analysed data from 25 patients between April 2019 and July 2020. 13 patients underwent surgical resections of lesions in close proximity of motor eloquent structures using intraoperative MEP-monitoring with placement of cortical strip electrodes, 12 patients underwent surgery requiring the use of transcranial motor evoked potentials. In all cases stimulation was done with a frequency of 0,25Hz, 0,5Hz and 1Hz for 2 minutes each. In the cases using transcranial MEP-monitoring stimulation was done before craniotomy and in the cases using the strip electrode stimulation was done after placement of the electrode and before resection of the lesion. In almost all cases peripheral nerve recording electrodes were placed in the thenar muscle. Potentials were recorded and later the data of the first 10 curves and last 10 curves of each series of measurements were averaged and compared for all measurements to see whether a significant change in potentials could be shown for series of measurements done with different frequencies.

Results: In the analysis of the 13 cases of neurophysiological data obtained by using a strip electrode as well as in the 12 cases of transcranial MEP-measurement no significant increase of potentials could be shown for higher frequency recordings in the analysis. No other adverse events were noted.

Conclusion: Neither in the group of transcranial nor in the group of cortical stimulation did an increase of the frequency of electrical stimulation lead to a significant change of potentials. This suggests that intraoperative motor evoked potentials during neurosurgical procedures can be used safely in high frequency to provide continuous intraoperative monitoring with high temporal resolution quickly showing if a decrease of potentials happens without the occurrence of a build-up effect of potentials.