Schizencephaly

Abstract

Schizencephaly is an uncommon congenital disorder of cerebral cortical development. Although a well-recognized cause of seizures and developmental deficits in children, previous reports describe the range of neurode-velopmental outcome in only 47 patients. We report the clinical and cranial imaging features of 47 children with unilateral open-lip (171, unilateral closed-lip (121, bilateral open-lip (121, and bilateral closed-lip (6) schizencephaly, as defined radiologically. The schizencephalic cleft occurred more often in the anterior than in the posterior neocortex. Children with closed-lip schizencephaly presented with hemiparesis or motor delay whereas patients with open-lip schizencephaly presented with hydrocephalus or seizures. Forty-three patients (91%) had associated cerebral developmental anomalies, most commonly absence of the septum pellucidum (45%) and focal cortical dysplasia (40%). There was a history of seizures in 57% of cases, a third of which were classified as difficult to control. Neurodevelopmental outcome was generally poor, with 51% of patients (24/47) having severe deficits, 32% of patients (15/47) having moderate impairment, and 17% of patients (8/47) having mild or no problems. Patients with closed-lip schizencephaly were more likely to have a mild to moderate outcome than those with open-lip type (78% versus 31%; p < 0.05). Children with unilateral schizencephaly had a mild or moderate outcome more frequently than those with bilateral lesions (62% versus 28%; p < 0.05). Children who had involvement of a single lobe accounted for 88% of those with mild outcomes and 53% of those with moderate outcomes. Unilateral closed-lip schizencephaly was associated with the best neurodevelopmental outcome; in contrast, 11 of 12 children with bilateral open-lip clefts had severe disabilities. Language development was significantly more likely to be normal in those children with unilateral schizencephaly than in those with bilateral clefts (48% versus 6%; p < 0.002). Thus, the presentation and outcome of children with schizencephaly are quite variable but are related to the extent of cortex involved in the schizencephalic defect.