To investigate the possible pathogenesis of post-seizure headache by brain imaging, vascular ultrasound, neuroelectrophysiology, blood indicators and other clinical markers.

Forty inpatients who had been treated at the Epilepsy Monitoring Center of Tianjin Huanhu Hospital were enrolled between October 2013 and October 2018, 20 patients with post-seizure headache as the experimental group, and other 20 patients without post-seizure headache as the control group. The serum 5-hydroxytryptamine (5-HT), nitric oxide (NO), and glutamic acid (Glu), transcranial Doppler (TCD), video electroencephalogram (VEEG) and magnetic resonance imaging (MRI) of each patient were measured before the epileptic seizure in both groups, within 5 minutes of headache after the cease of epileptic seizure in the experimental group, and within 5 minutes after the cease of epileptic seizure in the control group, respectively. The t-test was used to compare the differences of 5-HT, NO, Glu and blood flow changes in the front, middle, and posterior arteries of the brain during and after seizures. The χ² test was used to compare the difference of proportion of abnormal EEG discharges and the high signal ratio in diffusion-weighted imaging (DWI) in the two groups.

Compared with patients without headache after epilepsy, patients with post-seizure headache had significantly higher serum NO levels after seizures [(46.37±18.17) μmol/L vs (19.83±5.78) μmol/L, t=12.157, P=0.034]. The proportion of parietooccipital abnormal discharge was significantly higher than the control group (55.0% vs 25.0%, χ²=3.750, P=0.043). The diffuse discharge ratio was significantly lower than the control group (25.0% vs 60.0%, χ²=5.103, P=0.025). There were no significant differences in 5-HT, Glu, blood flow velocity in anterior cerebral artery, middle cerebral artery, posterior cerebral artery, and the proportion of intensive DWI signals between the two groups (P＞0.05).

The increase in serum NO level, the discharge of the parietooccipital, and the focal damage caused by epileptic seizures may be involved in the mechanism of post-seizure headache.