Page 171 - MEGIN Book Of Abstracts - 2023

regions where patients strongly differed from controls, OBJECTIVE To examine the usability of long-range
mainly in β frequencies, but also for δ and θ power. temporal correlations (LRTCs) in non-invasive localiza-
Network connectivity in GGE was heritable in frontal, tion of the epileptogenic zone (EZ) in refractory parietal
central, and inferior parietal brain areas and power in lobe epilepsy (RPLE) patients.
central, temporo-parietal, and subcortical structures.
Presence of generalized spike-wave activity during METHODS We analyzed 10 RPLE patients who had
recordings and medication were associated with the presurgical MEG and underwent epilepsy surgery. We
network patterns, whereas other clinical factors such as quantified LRTCs with detrended fluctuation analysis
age at onset, disease duration, or seizure control were (DFA) at four frequency bands for 200 cortical regions
not. estimated using individual source models. We correlat-
ed individually the DFA maps to the distance from the
CONCLUSION Metrics of brain oscillations are well resection area and from cortical locations of interictal
suited to characterize GGE and likely relate to genetic epileptiform discharges (IEDs). Additionally, three clini-
factors rather than the active disease or treatment. cal experts inspected the DFA maps to visually assess
High power and connectivity levels co-segregated in the most likely EZ locations.
patients with GGE and healthy siblings, predominantly
in the β band, representing an endophenotype of GGE. RESULTS The DFA maps correlated with the distance
to resection area in patients with type II focal cortical
Neurology (2021), Vol. 97, No. 2 (34045271) (5 citations) dysplasia (FCD) (p<0.05), but not in other etiologies.
Similarly, the DFA maps correlated with the IED loca-
tions only in the FCD II patients. Visual analysis of the
Detrended fluctuation analysis in the presurgical DFA maps showed high interobserver agreement and
evaluation of parietal lobe epilepsy patients (2021) accuracy in FCD patients in assigning the affected
hemisphere and lobe.
Auno, Sami; Lauronen, Leena; Wilenius, Juha; Peltola,
Maria; Vanhatalo, Sampsa; Palva, J Matias CONCLUSIONS Aberrant LRTCs correlate with the
resection areas and IED locations.
Epilepsia Helsinki, University of Helsinki and Helsinki Uni-
versity Hospital, Helsinki, Finland; Department of Clinical SIGNIFICANCE This methodological pilot study
Neurophysiology and BABA center, Children's Hospital, HUS demonstrates the feasibility of approximating cortical
Medical Imaging Center, University of Helsinki and Helsinki LRTCs from MEG that may aid in the EZ localization and
University Hospital (HUH), Helsinki, Finland; Neuroscience provide new non-invasive insight into the presurgical
Center, Helsinki Institute of Life Science, University of Helsinki, evaluation of epilepsy.
Helsinki, Finland. Electronic address: [email protected];
Epilepsia Helsinki, University of Helsinki and Helsinki Universi- Keywords: Detrended fluctuation analysis, Epilepsy sur-
ty Hospital, Helsinki, Finland; Department of Clinical Neuro- gery, Long-range temporal correlation, MEG
physiology and BABA center, Children's Hospital, HUS Medical
Imaging Center, University of Helsinki and Helsinki University Clinical neurophysiology: official journal of the
Hospital (HUH), Helsinki, Finland; BioMag Laboratory, HUS International Federation of Clinical Neurophysiology
Medical Imaging Center, Helsinki University Hospital(HUH), (2021), Vol. 132, No. 7 (34030053) (1 citation)
Helsinki, Finland; Department of Neuroscience and Biomedi-
cal Engineering, Aalto University, Finland; Centre for Cognitive
Neuroimaging, Institute of Neuroscience and Psychology,
University of Glasgow, United Kingdom; Neuroscience Center,
Helsinki Institute of Life Science, University of Helsinki, Hel-
sinki, Finland

 ontents  Index 150
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