title: Body weight lower limits of fetal postmortem MRI at 1.5 T.
abstract: OBJECTIVE
  To evaluate the diagnostic yield of postmortem magnetic resonance imaging (PM-MRI) compared with conventional autopsy in fetuses of early gestational age and low body weight.
  
  
  METHODS
  Fetuses of < 31 weeks' gestation that underwent 1.5-T PM-MRI and conventional autopsy were included. The findings of PM-MRI and conventional autopsy were reported blinded to each other. The reports of conventional autopsy and PM-MRI for each organ system (cardiovascular, neurological, abdominal, non-cardiac thoracic and musculoskeletal) were classified as either diagnostic or non-diagnostic. The likelihood of a non-diagnostic examination by PM-MRI was calculated according to fetal gestational age and body weight.
  
  
  RESULTS
  Full datasets were examined of 204 fetuses, with mean gestational age of 20.95 ± 3.82 weeks (range, 12.0-30.7 weeks) and body-weight range of 15.9-1872 g. Body weight was the most significant predictor of diagnostic yield of PM-MRI. There was 95% confidence that 90% of fetuses will show diagnostic images by PM-MRI for all five organ systems when fetal body weight is ≥ 535 g, but < 50% of fetuses will have all five systems diagnostic on PM-MRI when body weight is < 122 g.
  
  
  CONCLUSIONS
  PM-MRI is highly likely to provide adequate diagnostic images for fetuses with a body weight > 500 g. Below this weight, the diagnostic yield of standard 1.5-T PM-MRI decreases significantly. These data should help inform parents and clinicians on the suitability of performing PM-MRI in fetuses with low body weight. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.
authors.affiliation: Department of Radiology, Great Ormond Street Hospital for Children, London, UK.
authors.forename: N
authors.initials: N
authors.lastname: Jawad
authors.affiliation: Department of Pathology, Great Ormond Street Hospital for Children, London, UK.|Institute of Child Health, University College London, London, UK.
authors.forename: N J
authors.initials: NJ
authors.lastname: Sebire
authors.affiliation: Clinical Epidemiology, Nutrition and Biostatistics Section, UCL Institute of Child Health, London, UK.
authors.forename: A
authors.initials: A
authors.lastname: Wade
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science, London, UK.|Cardiorespiratory Division, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK.
authors.forename: A M
authors.initials: AM
authors.lastname: Taylor
authors.affiliation: Genetics and Genomic Medicine, UCL Institute of Child Health, London, UK.|Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK.
authors.forename: L S
authors.initials: LS
authors.lastname: Chitty
authors.affiliation: Department of Radiology, Great Ormond Street Hospital for Children, London, UK.|Institute of Child Health, University College London, London, UK.
authors.forename: O J
authors.initials: OJ
authors.lastname: Arthurs
mesh_terms: D000328:Adult; D001344:Autopsy; D001835:Body Weight; D004311:Double-Blind Method; D005260:Female; D005865:Gestational Age; D006801:Humans; D008279:Magnetic Resonance Imaging; D011237:Predictive Value of Tests; D011247:Pregnancy; D012189:Retrospective Studies; D050497:Stillbirth
keywords: conventional autopsy; fetal; perinatal; postmortem MRI