Serial neuroimaging studies in Sotos syndrome (cerebral gigantism syndrome).

To elucidate the mechanism of excessive size of the head in Soto syndrome, serial neuroimaging features from birth were reviewed in two patients. Macrocephaly shortly after birth was attributed to increased volume of the cerebral parenchyma itself (megalencephalon). Subsequent excessive size of the head was related to retention of cerebrospinal fluid in the ventricles and the subarachnoid spaces. Thus, macrocephaly in Sotos syndrome reflects two different mechanisms. The value of serial evaluation of intracranial structures is emphasized.