Adult-onset neurologic dysfunction associated with cortical malformations.

BACKGROUND AND PURPOSE Malformations of cerebral cortical development are common anomalies of the brain, typically causing developmental delay or seizures that are classically thought to begin in childhood. We present clinical and MR imaging data of 16 patients with cortical malformations in whom evidence of neurologic dysfunction was first noted in adulthood, and attempt to determine whether these malformations had any differentiating features from those presenting in childhood. METHODS Imaging studies and clinical records of 16 patients with adult-onset neurologic dysfunction were reviewed retrospectively. The patients ranged in age from 17 to 64 years (mean age, 35 years) at the time of imaging. Imaging findings were correlated with seizure history. RESULTS Fourteen patients had subependymal heterotopia (seven women, seven men), and two patients had closed-lip schizencephalies. Eleven patients had epilepsy, with age of onset ranging from 14 to 45 years (mean age, 22 years); four of them were successfully controlled by medication. The remaining five patients had no seizure disorder. All patients, except one, had normal intelligence. The bilaterality or multiplicity of location of heterotopias was not associated with the presence or absence of seizures, seizure frequency, or electroencephalographic results. CONCLUSION Subependymal heterotopia and small closed-lip schizencephaly may have minor clinical manifestations that are not evident until adulthood, or may, occasionally, never cause neurologic signs or symptoms whatsoever.