Abstract：Objective: To investigate the role of combined ultrasound and MRI in the prenatal diagnosis of fetal posterior fossa anomalies and to verify its clinical value. Methods: The imaging data of cases suspected of fetal posterior fossa anomalies by prenatal ultrasound in our hospital were analyzed retrospectively from January 2011 to December 2012. We reviewed prenatal ultrasonography, MRI imaging, and outcome of all the cases after delivery as well as early postnatal imaging studies. Results: 27 cases suspected of fetal posterior fossa anomalies by fetal sonography underwent MRI examination during the study period. 9 were found to have normal posterior fossa structures by fetal MRI. In the remaining 18 cases(66.7%), posterior fossa abnormalities suspected by fetal sonography were confirmed by fetal MRI, of which 11 were live-born and 10 underwent postnatal MRI. There was complete agreement in fetal and postnatal MRI diagnoses in 5 infants (50%). In 2 cases (20%) fetal and postnatal MRI diagnoses disagreed and postnatal MRI revealed additional anomalies in 3 cases(30%). Conclusion: Ultrasonography is an effective method for prenatal identification of fetal posterior fossa anomalies. Antenatal MRI serves to confirm the sonographic findings as well as offering additional diagnostic information. However, postnatal MRI follow-up should be strongly emphasized.
2015, Vol. 26 
