Comparison of diffusion-weighted imaging and MR elastography in staging liver fibrosis: a meta-analysis

Purpose To compare the diagnostic performance of diffusion-weighted imaging (DWI), gradient-recalled echo-based magnetic resonance elastography (GRE-MRE), and spin-echo echo-planar imaging-based MRE (SE-EPI-MRE) in liver fibrosis staging. Methods A systematic literature search was done to collect studies on the performance of DWI, GRE-MRE, and SE-EPI-MRE for diagnosing liver fibrosis. Pooled sensitivity, specificity, diagnostic odds ratio, positive and negative likelihood ratio, and a summary receiver operating characteristic (ROC) curve were estimated with a bivariate random effects model. Subgroup analyses on various study characteristics were performed. Results Sixty studies with a total of 6620 patients were included in the meta-analysis. Pooled sensitivity and specificity of GRE-MRE and SE-EPI-MRE showed high diagnostic accuracy and did not differ significantly. The area under the summary ROC curve for all stages of fibrosis differed significantly between DWI (0.83-0.88) and either GRE-MRE (0.95-0.97) or SE-EPI-MRE (0.95-0.99). Substantial heterogeneity was detected for all three imaging methods. Conclusions Both GRE-MRE and SE-EPI-MRE are highly accurate for detection of each liver fibrosis stage, with high potential to replace liver biopsy. Although DWI had a moderate accuracy in distinguishing liver fibrosis, it could be regarded as an alternative to MRE, since it is widely available and easily implemented in routine liver MRI.