The clinical characteristics and surgical outcome of 6 patients with intractable epilepsy and coexisting extratemporal porencephaly and hippocampal sclerosis are presented from the University of Alabama, Birmingham, AL. Of 24 patients with congenital porencephaly and epilepsy, 6 had a temporal lobe epileptogenic focus, and temporal lobe resection was performed in 5. The mean age at surgery was 31 years (range, 15-42 years), and the time from onset of epilepsy was 27 years (range, 14-41 years). Mean age of seizure onset was 4.3 years (range, 6 months to 10 years). Porencephalic cyst volume was 11% of total intracranial volume (range, 1% to 32%). Freedom from seizures occurred in all five patients, at mean follow-up of 47 months (range, 22-67 months). Antiepileptic drug therapy was continued but at lower doses. Hippocampal sclerosis was confirmed histopathologically. Children with congenital porencephaly and intractable epilepsy should be evaluated early, and temporal lobectomy should be considered if clinical, MRI, and EEG findings indicate a temporal lobe origin for seizures. [1]
COMMENT. A common ischemic cause for the congenital porencephalic cyst and hippocampal sclerosis is postulated, involving perinatal occlusion of the posterior cerebral artery. The most frequent origin of seizures associated with the dual pathology is the temporal lobe. The selective resection of the temporal epileptogenic focus might be considered as an alternative to hemispherectomy, which carries a higher morbidity in these patients.