In a two-years period, from a total of 5481 EEGs, we could select 25, corresponding to 22 patients, with PLEDs (prevalence of 0.45%). The group was composed by 13 males and 9 females, with age ranging from 5 months to 85 years. Main diagnosis was epilepsy of unknown etiology and brain tumor (22% each). The localization of PLEDs was mainly temporal region (54% of the whole group) and more frequent morphology was "delta triphasic wave" (a graphic pattern resembling sharp wave, but with longer duration) (Vz of total), followed by sharp biphasic wave and sharp wave-slow wave (29% each). Although 9 patients died it was not possible to determine prognostic value of PLEDs specifically for each pathological condition.