with indeterminate or discordant results from previous fibrosis testing
when transient elastography or acoustic radiation force impulse (ARFI) elastography is unsuitable or has not worked.
1.2 Further research is recommended (see the section on further research) on:
how the test results affect care decisions
the test accuracy or prognostic ability of LiverMultiScan
the test accuracy or prognostic ability of MRE.
Why the committee made these recommendations
Assessing what stage NAFLD is at can help to make decisions about care. Sometimes a biopsy is needed, which is invasive and can cause severe complications like bleeding or death. LiverMultiScan and MRE are non-invasive MRI-based tests that aim to assess the stage of NAFLD to help make decisions about care, and reduce biopsy use.
LiverMultiScan aims to identify a stage of NAFLD called non-alcoholic steatohepatitis (NASH). It is not clear how diagnosing NASH affects care decisions, partly because there are currently no medicines approved for treating NASH. This may change in the future, because there are medicines for NASH in clinical trials. Also, the clinical evidence on test accuracy and how well it can predict clinical outcomes (prognostic ability) is uncertain. There is only 1 low-quality study on whether using LiverMultiScan can reduce biopsy use.
MRE aims to identify how much liver scarring (fibrosis) there is. The company provided thresholds for staging fibrosis. There is no evidence assessing MRE's accuracy using the company's thresholds for advanced fibrosis and cirrhosis. There is also no evidence on how MRE might affect care decisions for the people who would have it in the NHS.
The cost effectiveness of the tests is likely to depend on how much they can reduce biopsy use. In the economic model, the tests were cost effective when assuming no biopsy was done after them. But, based on available evidence, clinical experts said they would be unlikely to use the tests without a confirmatory biopsy. When assuming confirmatory biopsy would be done after all positive MRI test results, the cost-effectiveness estimates for LiverMultiScan are higher than what NICE normally considers a cost-effective use of NHS resources. MRE may be cost effective but the estimates are uncertain, largely because the cost of using MRE in the NHS is uncertain.
More evidence is needed, particularly on how LiverMultiScan or MRE test results would affect decisions about care. Also, more information is needed about whether MRI-based tests help people make lifestyle choices to help prevent or slow NAFLD progression. So, research is recommended.