We performed a retrospective analysis to determine the prognostic accuracy of fetal MRI (feMRI) in predicting postnatal neurodevelopmental outcome.  Additionally, we measured the diagnostic accuracy of feMRI with an assessment of concordance between prenatal diagnosis by feMRI and the postnatal imaging diagnosis.

We identified all feMRI performed at CHEO over a 10 year period and assessed agreement between prenatal prognosis and postnatal outcome.  Prenatal prognosis was determined by a pediatric neurologist who reviewed the feMRI report and categorized each pregnancy as having a favourable, indeterminate or poor prognosis.   Assessment of postnatal neurodevelopmental outcome was made solely on the basis of the child’s Gross Motor Function Classification System (GMFCS) score and whether the child developed epilepsy.  Postnatal outcome was categorized as favourable, intermediate or poor.  We also assessed diagnostic accuracy of feMRI by comparing prenatal and postnatal imaging diagnosis.

We reviewed 145 feMRI – 114 were included in the assessment of diagnostic accuracy; 104 were included in the assessment of prognostic accuracy.  There was 93.0% agreement between prenatal and postnatal imaging diagnosis.  Prognosis was favourable in 44.2%, indeterminate in 50.0%, and poor in 5.8% of pregnancies.  There was 93.5% agreement between a favourable prenatal prognosis and a favourable postnatal outcome. 

A favourable prenatal prognosis is highly predictive of a favourable postnatal outcome.  Further studies are required to better understand the role of feMRI in prognosticating postnatal development, particularly in pregnancies with indeterminate and poor prognoses.