T1 ρ Relaxation of the liver: A potential biomarker of liver function.

Abstract

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). 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. 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). 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.