Grey matter band heterotopia or double cortex syndrome with a band of grey matter located deeply and almost parallel to the cortex with similar signal intensity; the double cortical layers are separated by a thin white matter layer. The overlying cortex is normal with no pachygyria, polymicrogyria or lissencephaly. The ventricles are slightly prominent in size for the patient's age.
No evidence of acute intracranial bleeding, recent infarct, significant focal mass effect, or hydrocephalus is seen. The basal cisterns are patent. The signal intensity of the cerebellum, and of the brainstem is within normal limits. No abnormal extra-axial fluid collection is visible. Flow voids of the major intracranial vessels appear grossly preserved. The paranasal sinuses and mastoid air cells are clear. No gross orbital mass.