title: Post-mortem cerebral magnetic resonance imaging T1 and T2 in fetuses, newborns and infants.
abstract: Post-mortem magnetic resonance imaging (PM MRI) of brain is increasingly used in clinical practice; understanding of normal PM contrast to noise ratio (CNR), T1 and T2 values relaxation times is important for optimisation and accurate interpretation of PM MRI.
  
  
  METHODS
  We obtained T1- and T2-weighted images at 1.5 T. In the first phase of the study, we calculated CNR in twelve brain regions in 5 newborn infants after death and compared this with CNR from 5 infants during life. In the second phase, we measured deep grey matter (GM) and white matter (WM) T1 post-mortem in 18 fetuses and T1 and T2 post-mortem 6 infants prior to autopsy.
  
  
  RESULTS
  Phase I: post-mortem T1- and T2-weighted CNRs were lower in most brain regions than during life. Phase II: compared with in vivo, all post-mortem images lacked GM-WM contrast and had high T2-weighted WM signal intensity. Mean (SD) post-mortem T1 in white and deep gray matter were respectively 1898 (327)ms and 1514 (202)ms in fetuses (p>0.05) and 1234 (180)ms and 1016 (161)ms in infants and newborns (p>0.05). Mean (SD) post-mortem T2 was 283 (11)ms in WM and 182 (18)ms in deep GM in infants and newborns (p<0.001).
  
  
  CONCLUSIONS
  Post-mortem T1 and T2 values are higher than those reported from live cases. The difference between T1 values in GM and WM reduce after death.
authors.affiliation: UCL Institute for Women's Health, 86-96 Chenies Mews, London, United Kingdom. s.thayyil@ich.ucl.ac.uk
authors.forename: Sudhin
authors.initials: S
authors.lastname: Thayyil
authors.forename: Enrico
authors.initials: E
authors.lastname: De Vita
authors.forename: Neil J
authors.initials: NJ
authors.lastname: Sebire
authors.forename: Alan
authors.initials: A
authors.lastname: Bainbridge
authors.forename: David
authors.initials: D
authors.lastname: Thomas
authors.forename: Roxanne
authors.initials: R
authors.lastname: Gunny
authors.forename: Kling
authors.initials: K
authors.lastname: Chong
authors.forename: Mark F
authors.initials: MF
authors.lastname: Lythgoe
authors.forename: Xavier
authors.initials: X
authors.lastname: Golay
authors.forename: Nicola J
authors.initials: NJ
authors.lastname: Robertson
authors.forename: Ernest B
authors.initials: EB
authors.lastname: Cady
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Taylor
mesh_terms: D001344:Autopsy; D001921:Brain / Q000473:pathology*; D005260:Female; D005333:Fetus; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011180:Postmortem Changes