Electromagnetic navigation systems and intraoperative neuromonitoring: can they be used in combination?
EANS Academy. Lavrador J. 09/25/19; 275646; EP03085
Mr. Jose Lavrador
Mr. Jose Lavrador

Access to this content is reserved for EANS members and attendees of this event. Click here to become an EANS member and gain your access to the full content of the EANS Academy


Abstract
Discussion Forum (0)
Rate & Comment (0)
Objective: To assess the reliability of multimodal intraoperative neuromonitoring (IOM) with the use of electromagnetic navigation systems
Design: Single-institution prospective cohort study
Methods: Patients requiring craniotomy for brain tumour, with no pre-operative focal deficits, operated using an electromagnetic navigation system (AxiEM - Medtronic®) were included. Motor Evoked Potentials (MEPs), Somatosensory Evoked Potentials (SSEPs), Electroencephalogram (EEG), and Electromyogram (EMG) were recorded and analysed with both AxiEM on and off. The neurological outcomes of the included patients were recorded.
Results: 16 patients were included (10 males/ 6 females, mean age 46 (46.375)). All patients had MEPs, SSEPs, EMG, and EEG recorded. Even though the raw acquisition is affected by the electromagnetic field (particularly the SSEPs), no significant difference was detected in the morphology, amplitude and latency of the different monitoring modalities (AxiEM off versus AxiEM on) after the proper software filter application. Adjustments to the frequency of SSEP stimulation and number of averages, as well as reductions to the lowpass filters were applied. To decrease artefact on the EMG and EEG, a notch filter was used. Placement of the ground needles on the opposite side of the bed to the AxiEM box improved impedance measurements and lessened artefactual muscle recordings. The mean intraoperative distance to the corticospinal tract during the tumour resections was 6.375mm. Post operatively, none of the patients developed new focal deficits.
Conclusions: The information provided by the intraoperative neuromonitoring in neuro-oncology patients is reliable for monitoring and mapping, as well as to detect intraoperative complications, when used in combination with electromagnetic navigation systems (AxiEM - Medtronic®) provided that the appropriate software filters and tools are applied.
Objective: To assess the reliability of multimodal intraoperative neuromonitoring (IOM) with the use of electromagnetic navigation systems
Design: Single-institution prospective cohort study
Methods: Patients requiring craniotomy for brain tumour, with no pre-operative focal deficits, operated using an electromagnetic navigation system (AxiEM - Medtronic®) were included. Motor Evoked Potentials (MEPs), Somatosensory Evoked Potentials (SSEPs), Electroencephalogram (EEG), and Electromyogram (EMG) were recorded and analysed with both AxiEM on and off. The neurological outcomes of the included patients were recorded.
Results: 16 patients were included (10 males/ 6 females, mean age 46 (46.375)). All patients had MEPs, SSEPs, EMG, and EEG recorded. Even though the raw acquisition is affected by the electromagnetic field (particularly the SSEPs), no significant difference was detected in the morphology, amplitude and latency of the different monitoring modalities (AxiEM off versus AxiEM on) after the proper software filter application. Adjustments to the frequency of SSEP stimulation and number of averages, as well as reductions to the lowpass filters were applied. To decrease artefact on the EMG and EEG, a notch filter was used. Placement of the ground needles on the opposite side of the bed to the AxiEM box improved impedance measurements and lessened artefactual muscle recordings. The mean intraoperative distance to the corticospinal tract during the tumour resections was 6.375mm. Post operatively, none of the patients developed new focal deficits.
Conclusions: The information provided by the intraoperative neuromonitoring in neuro-oncology patients is reliable for monitoring and mapping, as well as to detect intraoperative complications, when used in combination with electromagnetic navigation systems (AxiEM - Medtronic®) provided that the appropriate software filters and tools are applied.
Code of conduct/disclaimer available in General Terms & Conditions

By clicking “Accept Terms & all Cookies” or by continuing to browse, you agree to the storing of third-party cookies on your device to enhance your user experience and agree to the user terms and conditions of this learning management system (LMS).

Cookie Settings
Accept Terms & all Cookies