[Effect of eyes closure, eyes closed and photic stimulation on the epileptiform discharges in children with epilepsies].

OBJECTIVE

To investigate the effect of eyes closure and closed on the epileptiform discharges, and the relationship between eyes closure or closed sensitivity and photosensitivity.

METHODS

During video-EEG monitoring, open-close eyes tests and intermittent photic stimulation (IPS) under different eyes conditions were carried out in epilepsy patients. The eyes conditions were divided into eyes opened, eyes closure (the period immediately after closing of the eyes and only lasts for less than 3 s), and eyes closed (the period lasting for more than 3 s and persisting as long as the eyes remain closed). From 135 patients, 13 cases whose EEG showed eyes closure or closed sensitivity had been selected out for our study. The clinical, eyes closure or closed sensitivity and the relationship between eyes closure or closed sensitivity and photosensitivity were analyzed.

RESULTS

Of the 13 patients, 8 were female, and 5 were male. The age ranged from 6 years to 17 years (median 11 years). The age at onset of epilepsy ranged from 1.5 years to 14.5 years (median 9 years). Epileptiform discharges could be provoked by eyes closure in 10 of 13 patients, associated with photosensitivity in 8 patients. Of the 8 patients, 6 cases showed photosensitivity under eyes closure and only 4 cases showed photosensitivity under eyes closed. Eyes closed sensitivity had been seen in 3 patients, with photosensitivity in 2 patients. Evoked EEG patterns and discharges regions by eyes closure and eyes closed conditions had not obvious differential and might be strongly related to the types of epilepsies. The intensity and frequencies of photosensitivity under different eyes conditions were different. After valproate acid treatment, the eyes closure or closed sensitivity and photosensitivity improved in 4 cases, with improvement of photosensitivity prior to eyes conditions sensitivity.

CONCLUSIONS

Eyes closure and eyes closed could induce EEG paroxysms, which involved in some types of epileptic syndromes and appeared common in female patients. Eyes closure or closed sensitivity might coexist or be disassociated with photosensitivity. Testing eyes closure, eyes closed and IPS during EEG monitoring would contribute to finding the EEG discharges, further help to diagnose epilepsies and epileptic syndromes and guide treatment.