Background: Continuous electroencephalogram (EEG) monitoring after seizures may provide an early clue to the diagnosis of perinatal arterial ischemic stroke (PAIS). We aimed to explore EEG biomarkers and seizure patterns of PAIS within 7 days. Methods: Data of children with PAIS were retrospectively analyzed. Using multi-channel video electroencephalogram (vEEG) and amplitude-integrated electroencephalogram (aEEG), the patients were divided into three groups according to the monitoring start time after symptom onset: ≤48 h, 48-72 h, and 4-7 days. The characteristics of EEG activity and the law of seizures were compared across groups. Together with magnetic resonance imaging (MRI), the spatial correspondence between brain electrical activity and injury site was determined. Results: Of 21 children studied, 19 (90.47%) developed disease within 48 h of delivery. Abnormal sleep-wake cycle, abnormal fast-wave activity, abnormal wave activity, hemispheric asymmetry, electrographic seizures (ESz), and electroclinical seizures (ECSz) were more common in the ≤48 h group and 48-72 h group. Differences among all groups were statistically significant (P <0.01). The most common abnormal wave activity was sharp wave or freak wave, consistent with the MRI-confirmed injury site. ESz and ECSz were detected in 12 cases (92.31%) in the ≤48 h group and two cases (15.38%) in the 48-72 h group, 66.67% were clonic, and 91.67% were frequent seizures. ESz or ECSz were not detected in the 4-7-day group. The starting point of ESz or ECSz was consistent with the area of the lesion shown by MRI. Conclusions: Bi-hemispheric diffuse abnormal fast wave activity, sharp wave or freak wave activity in the local brain region, and ESz or ECSz initiated in the same brain region are EEG biomarkers indicating PAIS. The duration of ESz or ECSz triggered by PAIS was less than 72 h.

The authors have declared no competing interest.

This work was sponsored by Project 82101525 supported by the National Natural Science Foundation of China.

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