title: Cross-sectional and longitudinal evaluation of  liver volume and total liver fat burden in adults  with nonalcoholic steatohepatitis.
abstract: OBJECTIVE
  To explore the cross-sectional and longitudinal relationships between fractional liver fat content, liver volume, and total liver fat burden.
  
  
  METHODS
  In 43 adults with non-alcoholic steatohepatitis participating in a clinical trial, liver volume was estimated by segmentation of magnitude-based low-flip-angle multiecho GRE images. The liver mean proton density fat fraction (PDFF) was calculated. The total liver fat index (TLFI) was estimated as the product of liver mean PDFF and liver volume. Linear regression analyses were performed.
  
  
  RESULTS
  Cross-sectional analyses revealed statistically significant relationships between TLFI and liver mean PDFF (R 2 = 0.740 baseline/0.791 follow-up, P < 0.001 baseline/P < 0.001 follow-up), and between TLFI and liver volume (R 2 = 0.352/0.452, P < 0.001/< 0.001). Longitudinal analyses revealed statistically significant relationships between liver volume change and liver mean PDFF change (R 2 = 0.556, P < 0.001), between TLFI change and liver mean PDFF change (R 2 = 0.920, P < 0.001), and between TLFI change and liver volume change (R 2 = 0.735, P < 0.001).
  
  
  CONCLUSIONS
  Liver segmentation in combination with MRI-based PDFF estimation may be used to monitor liver volume, liver mean PDFF, and TLFI in a clinical trial.
authors.forename: An
authors.initials: A
authors.lastname: Tang
authors.forename: Joshua
authors.initials: J
authors.lastname: Chen
authors.forename: Thuy-Anh
authors.initials: TA
authors.lastname: Le
authors.forename: Christopher
authors.initials: C
authors.lastname: Changchien
authors.forename: Gavin
authors.initials: G
authors.lastname: Hamilton
authors.forename: Michael S
authors.initials: MS
authors.lastname: Middleton
authors.forename: Rohit
authors.initials: R
authors.lastname: Loomba
authors.forename: Claude B
authors.initials: CB
authors.lastname: Sirlin
mesh_terms: D000273:Adipose Tissue / Q000473:pathology; D000368:Aged; D000499:Allylamine / Q000031:analogs & derivatives / Q000627:therapeutic use; D000924:Anticholesteremic Agents / Q000627:therapeutic use; D000069472:Colesevelam Hydrochloride; D003430:Cross-Sectional Studies; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008099:Liver / Q000473:pathology; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease / Q000188:drug therapy / Q000473:pathology*; D009929:Organ Size
chemical_list: D000924:Anticholesteremic Agents; D000499:Allylamine; D000069472:Colesevelam Hydrochloride