Latest developments in post‐mortem foetal imaging

Abstract

A sustained decline in parental consent rates for perinatal autopsies has driven the development of less‐invasive methods for death investigation. A wide variety of imaging modalities have been developed for this purpose and include post‐mortem whole body magnetic resonance imaging (MRI), ultrasound, computed tomography (CT) and micro‐focus CT techniques. These are also vital for “minimally invasive” methods, which include potential for tissue sampling, such as image guidance for targeted biopsies and laparoscopic‐assisted techniques. In this article, we address the range of imaging techniques currently in clinical practice and those under development. Significant advances in high‐field MRI and micro‐focus CT imaging show particular promise for smaller and earlier gestation foetuses. We also review how MRI biomarkers such as diffusion‐weighted imaging and organ volumetric analysis may aid diagnosis and image interpretation in the absence of autopsy data. Three‐dimensional printing and augmented reality may help make imaging findings more accessible to parents, colleagues and trainees.

A pragmatic evidence-based approach to post-mortem perinatal imaging

“…Where Fig. 1 The benefits for conducting a perinatal autopsy for different stakeholders image-guided tissue samples are acquired, the investigation is termed a 'minimally invasive autopsy' (MIA) [6].…”

“…image-guided biopsy or laparoscopically assisted biopsy), the study is referred to as a 'minimally invasive autopsy' (MIA). Where no incisions are made to the body, and only imaging is acquired, this is termed a 'non-invasive autopsy' (NIA) [6] Smaller foetuses, weighing less than 500 g (post-mortem bodyweight) or aged less than 18-week gestation, are more challenging to image with standard imaging technology [14], and specialist techniques are required such as high-field MRI (> 7 T) or 'microfocus computed tomography' (i.e. micro-CT) [15].…”

“…image-guided biopsy or laparoscopically assisted biopsy), the study is referred to as a ‘minimally invasive autopsy’ (MIA). Where no incisions are made to the body, and only imaging is acquired, this is termed a ‘non-invasive autopsy’ (NIA) [ 6 ] …”

“…Following the loss of a baby, autopsy is the single most useful investigation after death, yielding additional information or diagnosis in 40–70% of cases [ 1 , 2 ], of which up to 50% may not have been clinically suspected [ 3 – 5 ]. Whilst > 90% of parents are offered an autopsy, the majority refuse this investigation, leading to low autopsy uptake rates (30–40%) [ 6 ]. Reasons for refusal include dislike of the invasive procedure, wanting to ‘protect’ the child from further harm as well as religious and cultural beliefs (Table 1 ) [ 7 ].…”

The use of MRI in fetal conditions amenable for antenatal management

“…They offer almost microscopical resolution and guide the pathologist in the precise extirpation of fetal tissue for further analysis . Shelmerdine et al review all methods that can be used for that purpose, including microCT, MRI, and postmortem US, with an emphasis on the additional information in relation to in vivo studies and how that information eventually improves counselling of parents …”