title: Quantification of ante-mortem hypoxic ischemic brain injury by post-mortem cerebral magnetic resonance imaging in neonatal encephalopathy.
abstract: Post-mortem (PM) magnetic resonance imaging (MRI) is increasingly used as an alternative to conventional autopsy in babies dying from neonatal encephalopathy. However, the confounding effect of post-mortem changes on the detection of ante-mortem ischemic injury is unclear. We examined whether quantitative MR measurements can accurately distinguish ante-mortem ischemic brain injury from artifacts using post-mortem MRI.
  
  
  METHODS
  We compared PM brain MRI (1.5 T Siemens, Avanto) in 7 infants who died with neonatal encephalopathy (NE) of presumed hypoxic-ischemic origin with 7 newborn infants who had sudden unexplained neonatal death (SUND controls) without evidence of hypoxic-ischemic brain injury at autopsy. We measured apparent diffusion coefficients (ADCs), T1-weighted signal intensity ratios (SIRs) compared to vitreous humor and T2 relaxation times from 19 predefined brain areas typically involved in neonatal encephalopathy.
  
  
  RESULTS
  There were no differences in mean ADC values, SIRs on T1-weighted images or T2 relaxation times in any of the 19 predefined brain areas between NE and SUND infants. All MRI images showed loss of cortical gray/white matter differentiation, loss of the normal high signal intensity (SI) in the posterior limb of the internal capsule on T1-weighted images, and high white matter SI on T2-weighted images.
  
  
  CONCLUSIONS
  Normal post-mortem changes may be easily mistaken for ante-mortem ischemic injury, and current PM MRI quantitative assessment cannot reliably distinguish these. These findings may have important implications for appropriate interpretation of PM imaging findings, especially in medico-legal practice.
authors.affiliation: Centre for Perinatal Neuroscience, Imperial College London, Du Cane Road, London W12 0HS, United Kingdom. Electronic address: p.montaldo@imperial.ac.uk.
authors.forename: Paolo
authors.initials: P
authors.lastname: Montaldo
authors.affiliation: Centre for Perinatal Neuroscience, Imperial College London, Du Cane Road, London W12 0HS, United Kingdom.
authors.forename: Badr
authors.initials: B
authors.lastname: Chaban
authors.affiliation: Centre for Perinatal Neuroscience, Imperial College London, Du Cane Road, London W12 0HS, United Kingdom.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Lally
authors.affiliation: Department of Histopathology, Great Ormond Street Hospital for Children NHS Foundation Trust, Great Ormond Street, London WC1 3JH, United Kingdom.
authors.forename: Neil J
authors.initials: NJ
authors.lastname: Sebire
authors.affiliation: Centre for Cardiovascular Imaging, Institute of Cardiovascular Science, University College London, Gower Street, London WC1E 6BT, United Kingdom.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Taylor
authors.affiliation: Centre for Perinatal Neuroscience, Imperial College London, Du Cane Road, London W12 0HS, United Kingdom.
authors.forename: Sudhin
authors.initials: S
authors.lastname: Thayyil
mesh_terms: D016477:Artifacts; D001344:Autopsy; D006801:Humans; D020925:Hypoxia-Ischemia, Brain / Q000175:diagnosis*; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011180:Postmortem Changes
keywords: Magnetic resonance imaging; Neonatal encephalopathy; Post-mortem