Potential clinical benefits and limitations of fetal virtopsy using high‐field MRI at 7 Tesla versus stereomicroscopic autopsy to assess first trimester fetuses

Abstract

Objective: The aim of this study was to establish the diagnostic accuracy of high-field magnetic resonance imaging (MRI) at 7 Tesla (T) compared with that of stereomicroscopic autopsy for assessing first trimester fetuses.Methods: Nine consecutive cases of first trimester fetuses resulting from spontaneous and therapeutic pregnancy termination were considered. The cases were divided into two groups according to gestational age: the Embryo Group with cases of nine to 10 gestational weeks (GWs) and the Fetus Group with cases of 13 GWs. The first group was scanned using three-dimensional fast imaging with steady state precession (3D FISP), and the second group was scanned using a two-dimensional (2D) turbo spin-echo high-resolution T2-weighted imaging (T2 WI) protocol. A radiologist and two embryologists interpreted the images. All cases were evaluated by invasive autopsy, with pathologist blinded to the imaging results. In total, the database included 270 items for evaluation (9 cases × 30 structures/case). Results:The global agreement between fetal high-field virtopsy and microscopic or stereomicroscopic autopsy was evaluated using 225 evaluation items visible by both methods. Overall, using microscopic examination and stereomicroscopic autopsy as the gold standard, fetal high-field virtopsy had a sensitivity of 94.6% [95% CI, 87.2-98.3] and a specificity of 97.6% [95% CI, 95-98.8]. The positive predictive value (PPV) was 93% [95% CI, 85.7-96.6], and the negative predictive value (NPV) was

Diagnostic value of virtual autopsy using pm-MRI at 3T on malformed second trimester fetuses vs classic autopsy

“…However, the results obtained are consistent with those previously published in literature [ 19 , 20 ]. Thayyil recommends that diagnostic accuracy of pm-MRI for cardiac assessment can be improved by three methods: by adding 3D techniques, by secondary image revision by a cardiovascular pediatric radiologist or by using a higher magnetic field [ 20 – 22 ]. Another explanation for the results obtained for the cardio-vascular system may be our incipient experience regarding the aspect of fetal cardiac MRI at 3T.…”

Patterning of fractures in a case of intimate partner homicide (IPH)

“…Identifying specific patterning of ante‐ and perimortem trauma, like the one presented in the current case, is of crucial importance for developing nations, who may have very high caseloads and limited resources to augment the analyses. So‐called “virtual autopsies” can be of great benefit in providing additional details in complex cases, such as those involving fetal and child remains [51]. These virtopsies, however, require full body radiology, computed tomography, or even magnetic resonance imaging and the expertise to analyze them [51,52], which may not be readily available in all mortuaries at the required frequencies.…”

“…So‐called “virtual autopsies” can be of great benefit in providing additional details in complex cases, such as those involving fetal and child remains [51]. These virtopsies, however, require full body radiology, computed tomography, or even magnetic resonance imaging and the expertise to analyze them [51,52], which may not be readily available in all mortuaries at the required frequencies. Trauma patterns, as demonstrated in the present case, can avoid committing otherwise vital resources to cases easily informed by a forensic anthropologist while also aiding in the identification of this type of trauma in virtopsies by pathologists.…”

Virtual autopsy and confirmation of normal fetal heart anatomy in the first trimester using three-dimensional (3D) reconstruction of histological sections

“…Ex vivo non-invasive imaging techniques, such as high-resolution 7–9.4 T magnetic resonance imaging (MRI) [ 6 , 7 , 8 ] and microfocus computed tomography (micro-CT) [ 9 , 10 ], were proposed as alternatives for autopsy in small fetuses, less than 22 gestational weeks (GW), where the information provided by conventional 1.5–3 T MRI has important limitations [ 11 , 12 , 13 ]. Still, we have only limited data regarding the detection of heart anomalies in first trimester fetuses and the equipment’s and expert’s availability is very low.…”