Recent findings show magnetic resonance elastography was more accurate for detecting liver fibrosis vs. transient elastography, and MRI-based proton density fat fraction was more accurate than controlled attenuation parameter for detecting steatosis, in patients with biopsy-proven nonalcoholic fatty liver disease.
“This is the first study in the Western Population that has done a rigorous head-to-head comparison between [magnetic resonance elastography] vs. Fibroscan for non-invasive quantification of fibrosis and [MRI-based proton density fat fraction] vs. [controlled attenuation parameter] for non-invasive quantification of steatosis with liver histology as the gold standard,” Rohit Loomba, MD, MHSc, director of the NAFLD Research Center, UC San Diego Health, and professor of medicine at UC San Diego School of Medicine, told Healio.com/Hepatology.
For this cross-sectional study, Loomba and colleagues used the histological scoring system for NAFLD from the NASH clinical research network scoring system and evaluated reports of 104 consecutive adults (56.7% women) who underwent magnetic resonance elastography (MRE), transient elastography (TE) and liver biopsy analysis between October 2011 and May 2016 at a tertiary medical center. They then used receiver operating characteristic (ROC) curve analyses to compare performances of MRE vs. TE for the diagnosis of fibrosis and MRI-based proton density fat fraction (PDFF) vs. controlled attenuation parameter (CAP) for diagnosis of steatosis.
“Although liver biopsy is the current gold standard for assessing NAFLD, its accuracy has been questioned because of sampling errors and variable intra- and inter-observer agreement. Moreover, biopsy is invasive, which limits use as a population screening tool,” the researchers wrote. “Thus, there is a need for accurate, noninvasive methods that can clinically assess NAFLD.”
MRE detected stage 1 or more fibrosis with an area under the ROC (AUROC) of 0.82 (95% CI, 0.74–0.91), which was significantly higher compared with TE (AUROC = 0.67; 95% CI, 0.56–0.78).
MRI-PDFF detected any steatosis with an AUROC of 0.99 (95% CI, 0.98–1), which was significantly higher compared with CAP (AUROC = 0.85; 95% CI, 0.75–0.96).
MRE detected an AUROC of 0.89 (95% CI, 0.83–0.96) for stage 2 fibrosis, AUROC of 0.87 (95% CI, 0.78–0.96) for stage 3 and AUROC of 0.87 (95% CI, 0.71-1.00) for stage 4, compared with TE AUROC values of 0.86 (95% CI, 0.77–0.95), 0.8 (95% CI, 0.67–0.93) and 0.69 (95% CI, 0.45–0.94).
MRI-PDFF detected grade 2 or 3 steatosis with AUROC values of 0.9 (95% CI, 0.82–0.97) and 0.92 (95% CI, 0.84–0.99) compared with CAP AUROC values of 0.7 (95% CI, 0.58–0.82) and 0.73 (95% CI, 0.58–0.89).
“Using prospective, head-to-head comparisons, we showed that MRI-based MRE and MRI-PDFF are significantly more accurate than ultrasound-based TE and CAP, respectively, for diagnosing fibrosis and steatosis in an American cohort of patients with biopsy-proven NAFLD,” the researchers concluded. “MRI-based techniques may be preferable to TE for accurate noninvasive assessment of NAFLD. Future studies are necessary to assess the clinical utility of MRI and TE for diagnosing fibrosis and steatosis in a multicenter, longitudinal design, both in observational and intervention studies,” adding that the cost-effectiveness of using these new methods must also be evaluated for the development of diagnostic strategies for the diagnosis of NAFLD-associated fibrosis and steatosis. – by Melinda Stevens
Disclosure: Loomba reports no relevant financial disclosures. One researcher reports consulting, advising and holding a position on the speakers bureau for Bayer; and received grants from GE Healthcare.