Fetal Neuroimaging: Ultrasound or MRI?

Abstract

Ultrasound (US) is the imaging method of choice before 20 weeks of gestation, as screening modality, where repeated examinations are required and where magnetic resonance imaging (MRI) is contraindicated or has failed. In the right hands, US appears to be the equal of MRI in most instances of fetal cerebral pathology. MRI is preferred where US would be expected to be difficult, such as a very obese patient and in instances where acute asphyxia or cerebral tuberous sclerosis is suspected. A combination of US and MRI is preferred for possible fetal central nervous system complications related to congenital cytomegaloviral infection, trauma, bleeding, tumors, or cerebellar bleeding or telangiectasia. Whichever modality is used, the final diagnosis of complex central nervous system pathology should be made in a multidisciplinary setting.