Lissencephaly Subcortical heterotopia Subcortical band heterotopia 2019-02-24T21:08:16Z A form of subcortical heterotopia with mislocalized gray matter within the white matter.It is defined as longitudinal bands of gray matter located deep to the cerebral cortex and separated from it by a thin layer of normal appearing white matter. It is part of the lissencephaly spectrum.