Schizencephaly is an uncommon congenital disorder of cerebral cortical
development. Although a well-recognized cause of seizures and develop
mental deficits in children, previous reports describe the range of ne
urodevelopmental outcome in only 47 patients. We report the clinical a
nd cranial imaging features of 47 children with unilateral open-lip (1
2), unilateral closed-lip (12), bilateral open-lip (12), and bilateral
closed-lip (6) sckizencephaly, as defined radiologically. The schizen
cephalic cleft occurred more often in the anterior than in the posteri
or neocortex. Children with closed-lip schizencephaly presented with h
emiparesis or motor delay whereas patients with open-lip schizencephal
y presented with hydrocephalus or seizures. Forty-three patients (91%)
had associated cerebral developmental anomalies, most commonly absenc
e of the septum pellucidum (45%) and focal cortical dysplasia (40%). T
here was a history of seizures in 57% of cases, a third of which were
classified as difficult to control. Neurodevelopmental outcome was gen
erally 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 schizencepha
ly 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 sch
izencephaly had a mild or moderate outcome more frequently than those
with bilateral lesions (62% versus 28%; p <0.05). Children who had inv
olvement of a single lobe accounted for 88% of those with mild outcome
s and 53% of those with moderate outcomes. Unilateral closed-lip schiz
encephaly 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 presentati
on and outcome of children with schizencephaly are quite variable but
are related to the extent of cortex involved in the schizencephalic de
fect.