| Abstract: | Purpose: We explored high‐frequency oscillations (HFOs) in scalp sleep electroencephalography (EEG) studies of patients with idiopathic partial epilepsy (IPE) of childhood in order to obtain a better understanding of the pathologic mechanisms underlying IPE. Methods: The subjects were 45 patients, including 32 with benign childhood epilepsy with centrotemporal spikes (BCECTS) and 13 with Panayiotopoulos syndrome (PS). A total of 136 EEG records were investigated through temporal expansion and filtering of traces and time‐frequency spectral analysis. Key Findings: HFOs with frequency of 93.8–152.3 Hz (mean 126.2 ± 13.6 Hz) in the band of ripples were detected in association with spikes in 97 records (71.3%). Time from last seizure to the EEG recording was significantly shorter in those with spike‐related HFOs than in the EEG recordings with spikes without HFOs (p = 0.006). Although time from last seizure reflects age, age at the time of recording was not significantly different between EEG studies with and without HFOs. Peak‐power values of the high‐frequency spots in time‐frequency spectra were significantly negatively correlated with time from last seizure (R2 = 0.122, p < 0.001) but not with age at the time of recording. Peak frequencies of the high‐frequency spectral spots were not significantly correlated with age at the time of recording or with time from last seizure. Significance: The close relationship between the generation of spike‐related HFOs and the period of active seizure occurrence indicated that HFOs may tell us more about epileptogenicity in IPE than the spikes themselves. Because there is a spectrum of pediatric epileptic disorders extending from the benign end of BCECTS to the encephalopathic end of epilepsy with continuous spike‐waves during slow‐wave sleep (CSWS), and HFOs that have already been detected in association with CSWS were more prominent than HFOs in IPE, intense spike‐related HFOs may indicate poor prognosis. |
