Familial periventricular nodular heterotopia.

We describe herein a 13-year-old girl, her 34-year-old mother and her 60-year-old grandmother who have periventricular heterotopic nodules. The mother has suffered from epileptic seizures since she was 15 years old, but the daughter and grandmother have had no epilepsy. They showed multiple uncalcified nodules on the lateral ventricular walls on CT. On MRI the intensity of the nodules was the same as that of the cerebral gray matter, suggesting heterotopia, and no other cerebral abnormalities were observed. Despite extensive examinations, neither have exhibited evidence of tuberous sclerosis. The periventricular nodular heterotopia observed in this family are a unique form of migration disorders, which may be caused by a dominant mutation.