Post‐mortem apparent resolution of fetal ventriculomegaly: evidence from magnetic resonance imaging

Abstract

This study aims to determine the accuracy of post-mortem magnetic resonance imaging (MRI) and autopsy for confirmation of sonographically detected fetal ventriculomegaly. This study uses retrospective review of fetuses with sonographically diagnosed ventriculomegaly, where the pregnancy was terminated and post-mortem examination was performed during a period in which post-mortem MRI was being offered. Sixteen cases were identified. In nine (56%), autopsy and/or post-mortem MRI confirmed the prenatal findings. In the other seven, both autopsy and post-mortem MRI demonstrated no ventriculomegaly, but antenatal MRI confirmed the ultrasound findings in 6/7 cases where it had been performed. Post-mortem investigations confirmed antenatal findings in 8/9 cases with severe ventriculomegaly (posterior horn measurement >15 mm), whereas only 2/7 in which ventriculomegaly was not confirmed had severe ventriculomegaly. Post-mortem examination, both by traditional neuropathological examination, and post-mortem MRI may fail to confirm prenatal ventriculomegaly in around half of cases. The post-mortem MRI findings indicate that this is due to resolution of ventriculomegaly rather than autopsy artefact, and is presumably a consequence of post-mortem fluid redistribution. Parents should be advised before termination of pregnancy that post-mortem confirmation of ventriculomegaly, especially in mild cases, may not be possible. Antenatal MRI may be a better approach for confirming prenatal ultrasound findings.