Can Postmortem Fetal MR Imaging Replace Autopsy?

ABSTRACT

PURPOSE: The purposes of this study were to compare postmortem fetal MRI findings with autopsy findings and to assess whether postmortem MRI can replace autopsy. MATERIALS AND METHODS: The study group consisted of 13 stillborn fetuses, seven that died immediately after birth, and five terminated because of anomalies seen on prenatal sonograms. A total 17 were male, and eight were female, and their gestational ages were from 20 to 41 (average; 28.2) weeks. Spin-echo T1-and T2-weight-ed axial, sagittal, and coronal MR images were obtained, and autopsy findings were divided into major and mi-nor. A major finding was defined as an anomaly or syndrome which caused fetal death or termination of the pregnancy; minor findings were classified, on the basis of gross inspection, as internal or external. MR images were retrospectively analyzed by two radiologists unaware of the autopsy findings, and by comparison with these, the postmortem MRI detection rates for major and minor findings was then determined. RESULTS: In seven of 25 fetuses, MR imaging revealed major findings, a detection rate of 100%. There were two cases of anencephaly, two of trisomy-18, and one each of hydrops fetalis with large cystic hygroma, diaphrag-matic hernia, and Dandy-Walker malformation. Twenty-three of 60 minor findings (38.3%) were detected by MRI. The detection rates for external and internal findings were 29.6%(8/27) and 45.5%(15/33), respectively. CONCLUSION: Although a limitation of our study is the low detection rate for minor findings, postmortem fetal MRI may help diagnose the major cause of fetal death.