Fetal magnetic resonance imaging and neurosonography in congenital neurological anomalies: supplementary diagnostic and postnatal prognostic value.

Objective: To compare the diagnostic conclusions between fetal neurosonography and MRI in the cases of congenital neurological abnormalities, and with postnatal clinical and imaging evaluation, when available.

Methods: A retrospective study of 28 patients who underwent a fetal MRI study for suspected congenital neurological anomalies. The diagnoses obtained by neurosonography and MRI were collected and compared. Both of them were compared with the final diagnosis when available by necropsy or postnatal evaluation. Postnatal imaging tests were performed only when clinically indicated.

Results: The indications for the fetal MRI examination were: fetal ventriculomegaly, posterior fossa anomalies, suspected midline defects, small-for-gestational-age cephalic biometry and confirmed congenital CMV infection. There was a good degree of agreement beyond chance between both techniques (kappa test = 0.76).

Conclusions: Both imaging modalities give a high-diagnostic performance with a good degree of agreement between them, when made by specialized staff. Fetal MRI is a valuable complementary tool to detailed neurosonography which allows an evaluation of the normal brain maturation from the second trimester. It also offers a higher diagnostic performance for some congenital abnormalities such as cortical development or acquired lesions.