BAND HETEROTOPIA OR DOUBLE CORTEX IN A MALE - BRIDGING STRUCTURES SUGGEST ABNORMALITY OF THE RADIAL GLIAL GUIDE SYSTEM

A moderately retarded Japanese boy, with a normal male karyotype (46,X Y), was diagnosed to have a subcortical band heterotopia or double cor tex syndrome. The band heterotopia was relatively thick compared with that of other patients reported. On T-2-weighted coronal MR sections, there were numerous radial linear structures between the cortex and th e band, probably representing the trace of radial fibers. He had no fa mily members with seizures or mental retardation. Over 50 described pa tients with this malformation have been female except two patients bri efly mentioned by several investigators. Band heterotopia or the doubl e cortex syndrome is inherited as a sex-linked dominant condition. Aff ected mothers may have affected daughters or sons with lissencephaly, suggesting a link between these disorders. This is the first detailed description of a male with band heterotopia.