[Late onset seizures in cerebral infarction--clinical study of late onset seizures in cortical branch infarction].

We retrospectively analyzed the clinical features, prognosis, CT scans and electroencephalograms in 527 patients with cerebral infarction in the Toranomon hospital between 1983 and 1990. CT scans revealed cortical involvement in 130 cases and subcortical infarcts in the territory of the perforating branch arteries in 397 cases. The mean duration of the follow up was 38.5 +/- 27 months (M +/- SD). Of these, late onset seizures developed in 5.69% (30/527). The incidence of seizures after cortical branch infarcts was 20% (26/130), which was significantly higher than that after subcortical infarcts (1%; 4/397) (p < 0.05). These late seizures could be either generalized or partial seizures. The interval between stroke and the onset of seizures was 2.4 years (mean), and 78% of late onset seizures developed within 3 years after the stroke. CT scans of the patients with late seizures showed that infarcted area was located mainly in the territory of the left middle cerebral artery. The incidence of late seizures was significantly higher in patients with left cortical infarction (12/41, 29.3%) than those with right one (6/29, 15.4%, p < 0.05). These results suggest that left-sided cortical involvement may have some liability to late onset seizures in patients with cerebral infarction. Further study on indication of prophylactic use of anticonvulsants might be requested in patients with right hemiparesis and aphasia.