Hemiatrophy of brain: antenatal ultrasonography and MRI/postnatal MRI diagnosis with the introduction of “shifted falx sign”

Dyke–Davidoff–Masson syndrome (DDMS) is an uncommon congenital/pediatric disorder diagnosed only with the help of imaging. Clinical features associated with it are hemiparesis, seizures, facial asymmetry, and mental retardation. We here present a case of DDMS diagnosed antenatally at 29 weeks gestational age during routine antenatal ultrasound examination. The patient was further evaluated and followed using both ultrasound and magnetic resonance imaging during antenatal and postnatal periods. The infant had unilateral hemiatrophy with the absence of anterior and middle cerebral arteries. We hereby also want to coin the term “shifted falx sign” as a diagnostic indicator for DDMS for the first time. To our knowledge, this is the earliest antenatally sonologically diagnosed case of the said pathology.