The value of EEG in the investigation of postapoplectic epilepsy

During the 5 years 1979-1983 61 patients within the county of Frederiksberg developed postapoplectic seizures after the age of 60. Of these patients EEG was performed on 48. These EEG's were compared to the EEG's from 25 patients of the same age with epilepsy due to cerebral tumors 33 patients with acute stroke and 24 patients with stroke sequelae who had not experienced seizures. Slow wave activity and foci were seen more often among patients with acute stroke than among patients with postapoplectic seizures whereas paroxysmal activity occurred less often in patients with acute stroke than among patients with postapoplectic seizures patients with stroke sequelae and patients with seizures due to cerebral tumours. Patients with stroke sequelae with proven hemispheric localization had focal abnormalities more often than patients with postapoplectic seizures but apart from this EEG difference between patients with postapoplectic seizures and patients with stroke sequelae or seizures due to brain tumours were not found. In 12 of the patients with postapoplectic seizures and in 20 of the patients with stroke sequelae without seizures EEG at the time of the acute stroke was available. Differences between patients with and patients without seizures were not found neither at the time of the acute stroke nor at the time of readmission due to stroke sequelae or due to onset of seizures. It is concluded that a routine EEG is without value in the diagnosis of postapoplectic seizures in the elderly.