Postmortem imaging of fetuses at early gestations: A comparison of microfocus computed tomography with postmortem magnetic resonance at 9.4T and postmortem ultrasound.

Abstract

To compare the diagnostic performance of postmortem ultrasound (PMUS), 9.4T magnetic resonance imaging (MRI) and microfocus computed tomography (micro-CT) for the examination of early gestation fetuses. Eight unselected fetuses (10-15weeks gestational age) underwent at least 2 of the 3 listed imaging examinations. Six fetuses underwent 9.4T MRI, four underwent micro-CT and six underwent PMUS. All operators were blinded to clinical history. All imaging was reported according to a prespecified template assessing 36 anatomical structures, later grouped into five regions: brain, thorax, heart, abdomen and genito-urinary. More anatomical structures were seen on 9.4T MRI and micro-CT than with PMUS, with a combined frequency of identified structures of 91.9% and 69.7% versus 54.5% and 59.6 (p<0.001; p<0.05) respectively according to comparison groups. In comparison with 9.4T MRI, more structures were seen on micro-CT (90.2% vs. 83.3%, p<0.05). Anatomical structures were described as abnormal on PMUS in 2.7%, 9.4T MRI in 6.1% and micro-CT 7.7% of all structures observed. However, the accuracy test could not be calculated because conventional autopsy was performed on 6 fetuses of that only one structure was abnormal. Micro-CT appears to offer the greatest potential as an imaging adjunct or non-invasive alternative for conventional autopsies in early gestation fetuses.