Guidance
2 The diagnostic test
Clinical need and practice
2.1 Liver fibrosis happens when persistent inflammation of the liver causes excessive scar tissue to build up in the organ and nearby blood vessels. The presence of scar tissue can impair overall liver function and limit blood flow which may lead to the death of liver cells. Advanced liver fibrosis can develop into cirrhosis, liver failure, portal hypertension and possibly needing a liver transplant. Liver fibrosis is caused by hepatitis, non-alcoholic fatty liver disease and alcohol-related liver disease.
2.2 Cirrhosis is a late-stage liver disease that happens when inflammation and fibrosis has spread throughout the liver and disrupts the shape and function of the liver. Cirrhosis usually develops silently after exposure to 1 or more risk factors such as alcohol misuse and hepatitis B or C which cause inflammation in the liver, or obesity. But, not everyone with inflammation of the liver will eventually develop cirrhosis. Untreated cirrhosis can cause liver failure, liver cancer or death.
2.3 NICE's guideline on assessing and managing cirrhosis in over 16s recommends using transient elastography to diagnose cirrhosis in people with hepatitis C, high alcohol consumption, diagnosed alcohol-related liver disease, or non-alcoholic fatty liver disease advanced fibrosis.
2.4 NICE's guideline on diagnosing and managing chronic hepatitis B recommends transient elastography as an initial test for liver disease in adults newly referred for assessment and for the annual reassessment of liver disease in adults who are not taking antiviral treatment.
2.5 NICE's guideline on assessing and managing non-alcoholic fatty liver disease states that the enhanced liver fibrosis test should be considered for people with non-alcoholic fatty liver disease to test for advanced liver fibrosis. Clinical experts highlighted that this test is not available everywhere, and FibroScan is often used instead of, or alongside, the enhanced liver fibrosis test. This is consistent with the British Society of Gastroenterology's guidance on non-alcoholic fatty liver disease and guidance on diagnosing and monitoring non-alcoholic fatty liver disease published in the British Medical Journal.
The intervention
FibroScan used outside secondary and specialist care
2.6 FibroScan (Echosens) is a non-invasive medical device that assesses liver fibrosis and cirrhosis by measuring the degree of liver stiffness. It can distinguish normal liver or minimal fibrosis from cirrhotic livers.
2.7 FibroScan uses proprietary vibration-controlled transient elastography to quantify liver stiffness, which is essentially a measure of the extent of liver scarring.
2.8 There are multiple products in the FibroScan range with different features, but all measure liver stiffness using transient elastography. The full list of devices can be found in table 1 of the scope.
2.9 Different sizes of probes (small, medium or extra-large) are available. The device comes with a medium probe. Small and extra-large probes are optional extras. The extra-large probe is designed to enhance signal penetration through deeper tissues, reducing device failure rates in people with obesity.
2.10 In this assessment, the intervention is FibroScan used outside secondary and specialist care. The population tested included only those who would have FibroScan in line with current NHS practice. The assessment focused on where the test should be done, rather than who should have the test.
2.11 Submissions provided by the company were based on the cost of the FibroScan 430 Mini+ at £48,000 both within and outside of secondary and specialist care settings.