Migraines for 9 months with a normal neurological exam. There are numerous nodules with grey matter signal characteristics along the bilateral lateral ventricular margins, right greater than left. THere is also prominence of the bilateral lateral ventricles, particularly the posterior portions, right more than left. There is prominence of the left parasagittal retrocerebellar cerebrospinal fluid spaces, associated with mild cerebellar asymmetry, in which the left cerebellar hemisphere is slightly smaller than the right. There is no evidence of intracranial hemorrhage or acute infarct. There is no midline shift or herniation. The major cerebral flow voids are intact. The orbits, skull, and scalp soft tissues are grossly unremarkable. There is a right maxillary sinus retention cyst.
Extensive bilateral lateral ventricular subependymal heterotopia with associated ventriculomegaly, right more than left, and mild cerebellar asymmetry.