Utility and cost evaluation of multiparametric magnetic resonance imaging for the assessment of non-alcoholic fatty liver disease.

BACKGROUND: Validated diagnostic tools that are accurate, cost effective and acceptable to patients are required for disease stratification and monitoring in NAFLD.

AIMS: To investigate the performance and cost of multiparametric MRI alongside existing biomarkers in the assessment of NAFLD.

METHODS: Adult patients undergoing standard of care liver biopsy for NAFLD were prospectively recruited at two UK liver centres and underwent multiparametric MRI, blood sampling and transient elastography withing 2 weeks of liver biopsy. Non-invasive markers were compared to histology as the gold standard.

RESULTS: Data were obtained in 50 patients and 6 healthy volunteers. Corrected T1 (cT1) correlated with NAFLD activity score (ρ = 0.514, P < .001). cT1, enhanced liver fibrosis (ELF) test and liver stiffness differentiated patients with simple steatosis and NASH with AUROC (95% CI) of 0.69 (0.50-0.88), 0.87 (0.77-0.79) and 0.82 (0.70-0.94) respectively and healthy volunteers from patients with AUROC (95% CI) of 0.93 (0.86-1.00), 0.81 (0.69-0.92) and 0.89 (0.77-1.00) respectively. For the risk stratification of NAFLD, multiparametric MRI could save £150,218 per 1000 patients compared to biopsy. Multiparametric MRI did not discriminate between individual histological fibrosis stages in this population (P = .068).

CONCLUSIONS: Multiparametric MRI accurately identified patients with steatosis, stratifies those with NASH or simple steatosis and reliably excludes clinically significant liver disease with superior negative predictive value (83.3%) to liver stiffness (42.9%) and ELF (57.1%). For the risk stratification of NAFLD, multiparametric MRI was cost effective and, combined with transient elastography, had the lowest cost per correct diagnosis.