Seizures after primary intracerebral hemorrhage.

We followed 123 patients with primary intracerebral hemorrhage (ICH), defined as bleeding without known precipitating cause except hypertension, for an average of 4.6 years or until death in order to determine the incidence, prevalence, and type of epileptic seizures. Twenty-five percent had seizures. In one-half of these, the seizures began within 24 hours of the hemorrhage. Survival table analysis predicted a potential cumulative seizure incidence of 50%, had all patients survived 5 years. Seizure incidence was high with bleeding into lobar cortical structures (54%), low with basal ganglionic hemorrhages (19%), and zero with thalamic hemorrhages. Within the basal ganglia, caudate involvement predicted seizures; within the cortex, temporal or parietal involvement predicted seizures. Although seizure incidence was high, prevalence of chronic epilepsy was much lower: 13% in 30-day to 2-year survivors and 6.5% in 2- to 5-year survivors. Seizure incidence is higher than previously reported after ICH because small lobar hemorrhages are the most epileptogenic and are now easily recognized with computed tomography.