Xin Kang

Acceptance, reliability and confidence of diagnosis of fetal and neonatal virtuopsy compared with conventional autopsy: A prospective study

To compare prospectively maternal acceptance of fetal and neonatal virtuopsy with that of conventional autopsy and to determine the confidence with which magnetic resonance (MR) virtuopsy can be used to diagnose normality/abnormality of various fetal anatomical structures.

Parental acceptance of minimally invasive fetal and neonatal autopsy compared with conventional autopsy

To determine parental acceptance of minimally invasive autopsy (MIA) involving postmortem imaging and organ tissue sampling compared with conventional autopsy and to compare the acceptability of percutaneous versus laparoscopic‐guided biopsy.

Magnetic resonance imaging in the normal fetal heart and in congenital heart disease

To evaluate prospectively the feasibility of magnetic resonance imaging (MRI) for assessment of the fetal heart for congenital heart disease (CHD).

Learning effect on perinatal post‐mortem magnetic resonance imaging reporting: single reporter diagnostic accuracy of 200 cases

The objective of the study is to compare diagnostic accuracy of perinatal post‐mortem magnetic resonance (PMMR) imaging against conventional autopsy, when reported by a single‐blinded observer for all organ systems following a period of initial experience.

A Longitudinal Study on Fetal Weight Estimation at Third Trimester of Pregnancy: Comparison of Magnetic Resonance Imaging and 2-D Ultrasound Predictions

Objective: To prospectively compare magnetic resonance (MR) estimation of fetal weight (MR-EFW) performed at third trimester with ultrasound (US) estimation of fetal weight (US-EFW) and actual birth weight, and to evaluate factors influencing fetal growth rate near term. Methods: US-EFW and MR-EFW were calculated at a median of 33.0 and 37.7 weeks of gestation in 37 fetuses and plotted on curve centiles to predict birth weights at 39.3 weeks of gestation. The median absolute relative errors for predicted US-EFW and MR-EFW were calculated. Regression analysis was used to investigate the effect of different variables on fetal growth rate at 35.2 weeks of gestation. Results: The relative error of actual birth weight as predicted by US at 33.0 weeks was significantly higher compared with MR (7.33 vs. 4.11%; p = 0.001). This was also the case for fetal weight predicted by US at 37.7 weeks as compared with MR (6.63 vs. 2.60%; p < 0.01). Fetal growth rate was significantly and independently positively associated with the mothers weight and with gestational age at estimation (p < 0.05 for both variables). Conclusion: Fetal weight estimates predicted using MR at third trimester are better than those given by prenatal US. Fetal growth rate depends on fetal and maternal characteristics.

Postmortem microfocus computed tomography for early gestation fetuses: a validation study against conventional autopsy

BACKGROUND: Perinatal autopsy provides useful clinical information in up to 40% of cases. However, there is a substantial unmet clinical need with regards to postmortem investigation of early gestation fetal loss for parents for whom standard autopsy is either not available or not acceptable. Parents dislike the invasive nature of autopsy, but current clinical imaging techniques do not provide high‐enough imaging resolution in small fetuses. We hypothesized that microfocus computed tomography, which is a rapid high‐resolution imaging technique, could give accurate diagnostic imaging after early gestation fetal loss. OBJECTIVE: The objective of the study was to evaluate the diagnostic accuracy of microfocus computed tomography for noninvasive human fetal autopsy for early gestation fetuses, with the use of conventional autopsy as the reference standard. STUDY DESIGN: We compared iodinated whole body microfocus computed tomography in 20 prospectively recruited fetuses (11–21 weeks gestation from 2 centers) with conventional autopsy in a double‐blinded manner for a main diagnosis and findings in specific body organs. Fetuses were prepared with 10% formalin/potassium tri‐iodide. Images were acquired with a microfocus computed tomography scanner with size‐appropriate parameters. Images were evaluated independently by 2 pediatric radiologists, who were blinded to formal perinatal autopsy results, across 40 individual indices to reach consensus. The primary outcome was agreement between microfocus computed tomography and conventional autopsy for overall diagnosis. RESULTS: Postmortem whole body fetal microfocus computed tomography gave noninvasive autopsy in minutes, at a mean resolution of 27&mgr;m, with high diagnostic accuracy in fetuses at <22 weeks gestation. Autopsy demonstrated that 13 of 20 fetuses had structural abnormalities, 12 of which were also identified by microfocus computed tomography (92.3%). Overall, microfocus computed tomography agreed with overall autopsy findings in 35 of 38 diagnoses (15 true positive, 18 true negative; sensitivity 93.8% [95% confidence interval, 71.7–98.9%], specificity 100% [95% confidence interval, 82.4–100%]), with 100% agreement for body imaging diagnoses. Furthermore, after removal of nondiagnostic indices, there was agreement for 700 of 718 individual body organ indices that were assessed on microfocus computed tomography and autopsy (agreement, 97.5%; 95% confidence interval, 96.1–98.4%), with no overall differences between fetuses at ≤14 or >14 weeks gestation (agreement, 97.2% and 97.9%, respectively). Within first‐trimester fetal loss cases (<14 weeks gestation), microfocus computed tomography analysis yielded significantly fewer nondiagnostic indices than autopsy examination (22/440 vs 48/348, respectively; P<.001). CONCLUSION: Postmortem whole‐body fetal microfocus computed tomography gives noninvasive, detailed anatomic examinations that are achieved in minutes at high resolution. Microfocus computed tomography may be preferable to magnetic resonance imaging in early gestation fetuses and may offer an acceptable method of examination after fetal loss for parents who decline invasive autopsy. This will facilitate autopsy and subsequent discussions between medical professionals who are involved in patient care and counselling for future pregnancies.

Postmortem examination of human fetuses: a comparison of 2-dimensional ultrasound with invasive autopsy

To assess the diagnostic accuracy of postmortem ultrasound performed by operators blinded to prenatal findings and to invasive autopsy results in fetuses at different gestational ages and to investigate the effect of various parameters on its diagnostic success.

Novel usage of microfocus computed tomography (micro‐CT) for visualisation of human embryonic development—Implications for future non‐invasive post‐mortem investigation

Whats already known about this topic? Accurate pathological assessment of small gestational age fetuses is challenging. Dating an embryo/fetus is essential to recognise expected human developmental stages and prevent misdiagnosis. What does this study add? Micro‐CT offers a non‐destructive, digital method for dating human embryos. The micro‐CT imaging here is of the earliest gestation human embryo published to date with corresponding pathology. It can provide an alternative to autopsy even at early stages of development.

Profile of women choosing the Harmony® Prenatal Test

ABSTRACT Introduction: The Harmony® Prenatal Test, a noninvasive cell-free DNA (cfDNA) method for major trisomies has been available since January 2013 at our unit, and tests were sent to the Ariosa Clinical Laboratory Improvement Amendments (CLIA) laboratory in California. From July 2017 onward, prenatal cfDNA has been reimbursed in Belgium for all pregnancies; however, since then samples are sent to a local laboratory. Little data are available on patient’s profile and choices toward cfDNA and on the performance of local technology transfer centers. Areas covered: The profiles and choices of women regarding this test were evaluated. Further, the performance of cfDNA at the local laboratory was compared to the one in California. Our results showed that women from the Netherlands, as compared to Belgium, were more likely to undergo cfDNA testing for maternal request and would be less likely to undergo karyotyping if cfDNA were unavailable, therefore are better candidates for cfDNA testing, when this is used as first-line screening. Expert commentary: Our findings highlight the importance of conducting these types of studies, before decisions about clinical implementation are made by national governments and ministries of health.

E1.4 First experiences and diagnostic utility of micro-ct for fetal autopsy

Background Perinatal autopsy remains poorly accepted by parents, despite yielding information that affects the management of future pregnancies in around 30% of cases. Microcomputed tomography (micro-CT) has shown promising results in the examination of ex-vivo fetal organs, and may provide diagnostic imaging in cases where traditional autopsy is challenging, and existing post mortem imaging techniques (CT and MRI) provide insufficient diagnostic resolution. Our objective was to examine whole fetuses non-invasively using micro-CT, and compare the findings with standard autopsy as the gold standard. Methods In this ethically approved double blinded study, terminated fetuses or miscarriages underwent iodinated micro-CT examination followed by conventional autopsy. Images were acquired using a Nikon XTH225ST microfocus-CT scanner with individual specimen image optimisation. Forty indices normally assessed at perinatal autopsy were evaluated for each imaging dataset by two independent reporters and a consensus report produced. Autopsies were performed blinded to the imaging findings by one of two perinatal pathologists. Results We examined 8 fetuses, with a gestational age range of 11–16 gestational weeks. 36/320 indices were non-diagnostic (11%), but there was agreement for 271/284 diagnostic indices (overall concordance of 95.4% (95% CI 92.3, 97.3%). In seven out of eight fetuses (87.5%), the same final diagnosis was made following micro-CT examination and autopsy examination; in one case, micro-CT was non-diagnostic. Ten false negatives indices included a VSD, laryngeal anomaly, ambiguous genitalia and incomplete bowel rotation, none of which changed the overall diagnosis. Three apparent false positives on micro CT were a cloacal anomaly, incidental cystic neck lesion and thymic atrophy, which were not detected at autopsy. Conclusion Micro-CT of early gestation whole fetuses can provide highly accurate datasets with three-dimensional renderings of complex disease processes. This approach confirms the potential of this technology for non-invasive examination of small fetuses.