Photoparoxysmal responses.

ABSTRACT

Sixty-five outpatients with photoparoxysmal response (PPR) during routine EEG were studied. The PPR showed prevalence in women (75.4%). Seizures were found in 66.1% of cases. The rest recordings were abnormal in 41.8% with prevalence of generalized paroxysm. Eight patterns of PPR were observed, being polyspike mixed to slow wave the most frequent (53%). The epileptic group showed a bimodal distribution in the several bands of photic stimulation, near 8 and 20-24 Hz. A sustained paroxysmal abnormality persisting after the photic stimulation was present in 6 epileptic patients.