title: T1 ρ Relaxation of the liver: A potential biomarker of liver function.
abstract: OBJECTIVE
  To investigate the diagnostic potential of T1 ρ relaxation for assessing liver function, liver fibrosis, or liver necroinflammation in patients with chronic liver disease (CLD).
  
  
  METHODS
  We obtained T1 ρ maps of the liver for 53 patients with or without CLD. We measured the T1 ρ values of the liver and correlated them with the results of laboratory tests and histological examinations. Pearson's correlation coefficients (r) were calculated between the T1 ρ values and blood serum parameters including the retention rates at 15 minutes after an injection of indocyanine green (ICG-R15). Spearman's rank correlation coefficients were calculated between the T1 ρ values and the scores of liver fibrosis or liver necroinflammation.
  
  
  RESULTS
  The T1 ρ values showed significant positive correlations with the serum levels of total bilirubin (r = 0.31, P < 0.05), direct bilirubin (r = 0.32, P < 0.05), and ICG-R15 (r = 0.46, P < 0.05), and significant negative correlations with the serum levels of albumin (r = -0.33, P < 0.05) and γ-glutamyl transpeptidase (r = -0.28, P < 0.05). However, there were no significant correlations between the T1 ρ value and the scores of liver fibrosis (P = 0.95) or liver necroinflammation (P = 0.86).
  
  
  CONCLUSIONS
  T1 ρ relaxation has potential as a biomarker of liver function in patients with CLD. However, it may not be suitable to estimate liver fibrosis or liver necroinflammation.
authors.affiliation: Department of Radiology Informatics and Network, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Yukihisa
authors.initials: Y
authors.lastname: Takayama
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Nishie
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Asayama
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ushijima
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Okamoto
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Fujita
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Morita
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Fukuoka, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Shirabe
authors.affiliation: Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kotoh
authors.affiliation: Department of Anatomic Pathology, Pathological Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Kubo
authors.affiliation: Philips Electronics Japan, Tokyo, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Okuaki
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Honda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005240:Feasibility Studies; D005260:Female; D006505:Hepatitis / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008103:Liver Cirrhosis / Q000473:pathology* / Q000503:physiopathology*; D008111:Liver Function Tests / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: MRI; T1ρ (T1rho); chronic liver disease; liver fibrosis; liver function; liver necroinflammation