CONGENITAL PORENCEPHALY AND HIPPOCAMPAL SCLEROSIS - CLINICAL-FEATURESAND EPILEPTIC SPECTRUM

We studied clinical features and seizure localization in 14 patients w ith porencephaly and intractable seizures. Perinatal complications wer e present in nine patients, childhood febrile convulsions in two, cong enital hemiparesis in 12, and intellectual impairment in seven. Ten pa tients had psychoparetic complex partial seizures (CPS), three had sen sorimotor simple partial seizures, and one had generalized tonic-cloni c seizures. Surface EEG showed temporal onset in nine patients (one bi temporal) and extratemporal onset in four. MRI showed porencephaly in the distribution of the middle cerebral artery in eight patients, post erior cerebral in three, internal carotid in one, and multiple vessels in two. MR-based volumetry revealed hippocampal formation atrophy in 13 patients (eight unilateral and five bilateral) and amygdalar atroph y in 10 patients (nine unilateral and one bilateral). Hippocampal form ation atrophy was concordant with CPS semiology in 10 patients (71%) a nd with EEG temporal localization in nine patients, Two patients had p athologic confirmation of mesial temporal sclerosis and were seizure f ree after temporal lobectomy. We conclude that mesial temporal scleros is often coexists with porencephaly and is the likely seizure focus in the presence of concordant electroclinical data. This recognition imp lies that effective surgical intervention can be offered to certain pa tients with porencephaly-related seizure disorders. The dual pathology and association with perinatal cerebral vascular occlusion suggest a common ischemic pathogenesis.