A semi-automated method for non-invasive internal organ weight estimation by post-mortem magnetic resonance imaging in fetuses, newborns and children

doi:10.1016/j.ejrad.2008.07.013

European Journal of Radiology

Volume 72, Issue 2, November 2009, Pages 321-326

https://doi.org/10.1016/j.ejrad.2008.07.013 Get rights and content

Abstract

Magnetic resonance (MR) imaging allows minimally invasive autopsy, especially when consent is declined for traditional autopsy. Estimation of individual visceral organ weights is an important component of traditional autopsy.

Objective

To examine whether a semi-automated can be used for non-invasive internal organ weight measurement using post-mortem MR imaging in fetuses, newborns and children.

Methods

Phase 1: In vitro scanning of 36 animal organs (heart, liver, kidneys) was performed to check the accuracy of volume reconstruction methodology. Real volumes were measured by water displacement method. Phase 2: Sixty-five whole body post-mortem MR scans were performed in fetuses (n = 30), newborns (n = 5) and children (n = 30) at 1.5 T using a 3D TSE T2-weighted sequence. These data were analysed offline using the image processing software Mimics 11.0.

Results

Phase 1: Mean difference (S.D.) between estimated and actual volumes were −0.3 (1.5) ml for kidney, −0.7 (1.3) ml for heart, −1.7 (3.6) ml for liver in animal experiments. Phase 2: In fetuses, newborns and children mean differences between estimated and actual weights (S.D.) were −0.6 (4.9) g for liver, −5.1 (1.2) g for spleen, −0.3 (0.6) g for adrenals, 0.4 (1.6) g for thymus, 0.9 (2.5) g for heart, −0.7 (2.4) g for kidneys and 2.7 (14) g for lungs. Excellent co-correlation was noted for estimated and actual weights (r² = 0.99, p < 0.001). Accuracy was lower when fetuses were less than 20 weeks or less than 300 g.

Conclusion

Rapid, accurate and reproducible estimation of solid internal organ weights is feasible using the semi-automated 3D volume reconstruction method.

Section snippets

Aims

(1)
To examine the accuracy of 3D volume reconstruction software by in vitro MR scanning of solid animal organs.
(2)
To investigate whether this method can be used for rapid and accurate non-invasive estimation of visceral organ weights in fetuses, newborns and children by whole body post-mortem MR imaging.

Methods

This study was performed as part of a large ongoing prospective multicentric study on post-mortem MR and CT imaging with percutaneous biopsy in 600 cases including fetuses, newborns and children, which compares “less invasive autopsy” to “conventional autopsy” in a double-blinded way (MaRIAS: Magnetic Resonance Autopsy Imaging Study). MR imaging was performed using one of the four, 1.5 T MR scanners (Avanto, Siemens Medical Systems, Erlangen, Germany). The study was carried out in two phases.

Phase 1 experiments (animal scans)

Automated estimation was possible with all in vitro animal organ scans (12 livers, 12 hearts and 12 kidneys) organs. Total volume estimation time from the MR images using Mimics was 1–2 min per organ. There was excellent agreement between the methods for all the three organs: kidney (r² = 0.99, p < 0.001), heart (r² = 0.99, p < 0.001) liver (r² = 0.99, p < 0.001) and there was no significant bias (Fig. 2). Repeated measurements (four times) using four different upper and lower thresholds (1100/2700,

Discussion

In this study, we demonstrate for the first time that semi-automated MR 3D volume reconstruction provides an accurate, reproducible, non-invasive method for measuring the weight of solid visceral organs in infants and children and fetuses greater than 20 weeks gestation. This study may have major implications for the utilisation of post-mortem MR imaging and can be considered as the first step towards less invasive autopsy. Moreover, this technique can be used for non-invasive estimation of

Conflict of Interest

None.

Funding

The work for this project is funded by the UK Department of Health (0550004) and the British Heart Foundation (CI/05/010); neither funding body had no role in analysis of data, results or conclusions of the study. SS is funded by a BHF PhD fellowship, AMT, NJR, NJS are funded by Higher Education Funding Council for England (HEFCE). This work was undertaken at GOSH, ICH, UCLH/UCL who received a proportion of funding from the United Kingdom Department of Health's NIHR Biomedical Research Centres

Acknowledgements

We are indebted to Dr. Alistair Parker, who has guided through the process of this post-mortem project and to Joyce Epstein (Foundation of Sudden Infant Death) for advising regarding the recruitment of SUDI cases.

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View full text

A semi-automated method for non-invasive internal organ weight estimation by post-mortem magnetic resonance imaging in fetuses, newborns and children

Abstract

Objective

Methods

Results

Conclusion

Section snippets

Aims

Methods

Phase 1 experiments (animal scans)

Discussion

Conflict of Interest

Funding

Acknowledgements

Lancet

Lancet

Lancet

Forensic Sci Int

Postmortem fetal MR imaging: comparison with findings at autopsy

Am J Roentgenol

Perinatal necropsy by magnetic resonance imaging

Lancet

Perinatal necropsy by magnetic resonance imaging

Lancet

Perinatal and infant autopsy

Arch Dis Child Fetal Neonatal Ed

Critical evaluation of elective termination of pregnancy in a tertiary fetal medicine center during 43 months: correlation of prenatal diagnosis findings and postmortem examination

Prenat Diagn