Abstracts

Abnormal maturation of surviving cerebral cortex following late prenatal or perinatal hypoxic [ndash] ischemic brain injuries have been related to the genesis of acquired (or destructive) cortical dysplasia, postmigrational polymicrogyria, and ulegyria. These conditions have been only sporadically noted in series of patients operated for epilepsy. Our work illustrates the spectrum of pathological findings in epileptic children with perinatal brain injuries and localized dysgiria on MRI, and evaluates the role of surgery for seizure control. Three boys and one girl (aged 9 to 13 years, mean 10 years ) are reported. All showed: 1) a previous history of perinatal complications, 2)visual and/or cognitive deficits, 3) MRI findings characterized by atrophy and dysgyria with small or mushroom-shape gyri, associated with hyperintensity in immediately subcortical areas, and 4) focal refractory epilepsy, surgically treated following complete presurgical evaluation. In three patients the lesion affected mainly the occipital lobes. Despite clear bilateral MRI involvement in 2, unilateral occipital seizure onset was documented in all, which led to unilateral cortical resection. The other patient had congenital hemiplegia and startle-induced seizures, with a lesion involving the hole hemisphere, and was treated by functional hemispherectomy. Pathological studies showed: 1) neuronal loss and gliosis at the basis of the gyri (2 cases), 2) four-layered cortex with associated laminar necrosis and subpial gliosis (1 case); 3) cytoarchitectural dysplasia (3 cases), 4) dual pathology (hippocampal sclerosis, 1 case). Seizure outcome has been good or excellent in all cases (Engel class I- 3 cases, Engel class II- 1 case). Children affected by localized dysgyria related to perinatal brain injuries and refractory focal epilepsy can be good surgical candidates, including patients with bilateral occipital lesions. A continuum between ulegyria and destructive cortical dysplasia is suggested.