Micro-CT and high-field MRI for studying very early post-mortem human fetal anatomy at 8weeks of gestation.

Abstract

This study involved very early post-mortem (PM) examination of human fetal anatomy at 8weeks of gestation (WG) using whole-body multimodal micro-imaging: micro-CT and high-field MRI (HF-MRI). We discuss the potential place of this imaging in early first-trimester virtual autopsy. We performed micro-CT after different contrast-bath protocols including diffusible iodine-based contrast-enhanced (dice) and HF-MRI with a 9.4T machine with qualitative and quantitative evaluation and obtained histological sections. Nine fetuses were included: the crown-rump length was 10-24mm and corresponded to 7 and 9 WG according to the Robinson formula. The Carnegie stages were 17-21. Dice micro-CT and HF-MRI presented high signal to noise ratio, >5, according to the Rose criterion, and for allowed anatomical phenotyping in these specimens. Imaging did not alter the histology, allowing immunostaining and pathological examination. PM non-destructive whole-body multimodal micro-imaging: dice micro-CT and HF-MRI allows for PM human fetal anatomy study as early as 8 WG. It paves the way to virtual autopsy in the very early first trimester. Obtaining a precision phenotype, even regarding miscarriage products, allows a reverse phenotyping to select variants of interest in genome-wide analysis, offering potential genetic counseling for bereaved parents.