AUTHOR=Chen Jianhua , Zhou Xiangqin , Jin Liri , Lu Qiang , Sun Heyang , Liu Qing , Huang Yan 

TITLE=Can Spectral Power Be Used as a Candidate Seizure Marker of the Periodic Discharges Pattern?

JOURNAL=Frontiers in Neurology

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2021.642669

DOI=10.3389/fneur.2021.642669

ISSN=1664-2295

ABSTRACT=<p><bold>Introduction:</bold> It remains controversial whether the periodic discharges (PDs) pattern is an ictal or interictal phenomenon. The aims of the study are to apply time-frequency and power spectrum analysis to study the PDs pattern and prediction of seizures.</p><p><bold>Methods:</bold> We retrospectively searched continuous electroencephalography (cEEG) recordings to identify patients exhibiting the PDs pattern. Artifact-free cEEG segments demonstrating the PDs pattern with stable baselines were chosen for time-frequency and power spectrum analysis.</p><p><bold>Results:</bold> In total, 72 patients (1.3%) exhibited the PDs pattern, with a mean age 36.0 ± 20.7 years (range, 8–76 years). The median spectral power of PDs with a length of 60 s was 70.94 μV<sup>2</sup> and that of PDs with a length of 20 s was 195.80 μV<sup>2</sup>. During follow-up, patients with spectral power of PDs of length 60 and 20 s lower than 28.65 and 36.09 μV<sup>2</sup>, respectively, exhibited no seizure. For predicting seizures, when the spectral power for PDs of 60 and 20 s equaled to 17.26 and 21.40 μV<sup>2</sup>, respectively, the diagnostic sensitivity was 100% and specificity was 86%. The locations of maximal spectral power of PDs, crude seizure onset zone (SOZ) judged from scalp EEG, and the most prominent regions of hyper- or hypo-metabolism on FDG-PET were congruent.</p><p><bold>Conclusions:</bold> Spectral power might be a candidate seizure marker of the PDs pattern. High spectral power predicted a high risk of seizures, and low spectral power was associated with a low risk of seizures.</p>