Sándor Beniczky1, Lene Duez2, Michael Scherg3, Peter Orm Hansen2, Hatice Tankisi2, Per Sidenius4, Anne Sabers5, Lars Hageman Pinborg5, Peter Uldall6, Anders Fuglsang-Frederiksen2. 1. Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark; Department of Clinical Neurophysiology, Danish Epilepsy Centre, Dianalund, Denmark. Electronic address: sbz@filadelfia.dk. 2. Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark. 3. Research Department, BESA GmbH, Graefelfing, Germany. 4. Department of Neurology, Aarhus University Hospital, Aarhus, Denmark. 5. Department of Neurology and Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark. 6. Department of Paediatrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
Abstract
OBJECTIVE: Reviewing magnetoencephalography (MEG) recordings is time-consuming: signals from the 306 MEG-sensors are typically reviewed divided into six arrays of 51 sensors each, thus browsing each recording six times in order to evaluate all signals. A novel method of reconstructing the MEG signals in source-space was developed using a source-montage of 29 brain-regions and two spatial components to remove magnetocardiographic (MKG) artefacts. Our objective was to evaluate the accuracy of reviewing MEG in source-space. METHODS: In 60 consecutive patients with epilepsy, we prospectively evaluated the accuracy of reviewing the MEG signals in source-space as compared to the classical method of reviewing them in sensor-space. RESULTS: All 46 spike-clusters identified in sensor-space were also identified in source-space. Two additional spike-clusters were identified in source-space. As 29 source-channels can be easily displayed simultaneously, MEG recordings had to be browsed only once. Yet, this yielded a global coverage of the recorded signals and enhanced detectability of epileptiform discharges because MKG-artefacts were suppressed and did not impede evaluation in source-space. CONCLUSIONS: Our results show that reviewing MEG recordings in source-space is accurate and much more rapid than the classical method of reviewing in sensor-space. SIGNIFICANCE: This novel method facilitates the clinical use of MEG.
OBJECTIVE: Reviewing magnetoencephalography (MEG) recordings is time-consuming: signals from the 306 MEG-sensors are typically reviewed divided into six arrays of 51 sensors each, thus browsing each recording six times in order to evaluate all signals. A novel method of reconstructing the MEG signals in source-space was developed using a source-montage of 29 brain-regions and two spatial components to remove magnetocardiographic (MKG) artefacts. Our objective was to evaluate the accuracy of reviewing MEG in source-space. METHODS: In 60 consecutive patients with epilepsy, we prospectively evaluated the accuracy of reviewing the MEG signals in source-space as compared to the classical method of reviewing them in sensor-space. RESULTS: All 46 spike-clusters identified in sensor-space were also identified in source-space. Two additional spike-clusters were identified in source-space. As 29 source-channels can be easily displayed simultaneously, MEG recordings had to be browsed only once. Yet, this yielded a global coverage of the recorded signals and enhanced detectability of epileptiform discharges because MKG-artefacts were suppressed and did not impede evaluation in source-space. CONCLUSIONS: Our results show that reviewing MEG recordings in source-space is accurate and much more rapid than the classical method of reviewing in sensor-space. SIGNIFICANCE: This novel method facilitates the clinical use of MEG.
Authors: Mateusz Rusiniak; Harald Bornfleth; Jae-Hyun Cho; Tomasz Wolak; Nicole Ille; Patrick Berg; Michael Scherg Journal: Front Neurosci Date: 2022-03-10 Impact factor: 4.677