A rare case of hemimegalencephaly diagnosed prenatally.

Hemimegalencephaly (HME), or unilateral megalencephaly, is a rare congenital brain malformation defined as overgrowth of one cerebral hemisphere or part of it resulting from abnormal cortical development and neuronal migration. However, cortical developmental abnormalities are rarely diagnosed prenatally. This is the reason for our study, in which we describe and compare ultrasound and MRI findings in a fetus with HME.