From the Guidelines
Hepatosteatosis can be effectively evaluated through non-invasive methods such as imaging techniques and blood-based biomarkers, reducing the need for liver biopsy. These methods prioritize patient safety and quality of life by minimizing the risks associated with invasive procedures.
Non-Invasive Evaluation Methods
- Imaging techniques:
- Ultrasound is the most commonly used first-line test due to its wide availability, safety, and relatively low cost, with good sensitivity for detecting moderate to severe fatty infiltration 1.
- Computed Tomography (CT) scans can quantify liver fat by measuring liver attenuation, but its diagnostic performance for mild steatosis is suboptimal and it raises concerns about radiation hazards 1.
- Magnetic Resonance Imaging (MRI), particularly MRI-proton density fat fraction (MRI-PDFF) and magnetic resonance spectroscopy (MRS), provides the most accurate non-invasive quantification of liver fat 1.
- Transient elastography (FibroScan) with controlled attenuation parameter (CAP) measurement can simultaneously assess both liver stiffness (fibrosis) and fat content, with a high area under the receiver operating characteristic curve (AUC) for diagnosing moderate to severe steatosis 1.
Blood-Based Biomarkers
- Liver function tests (ALT, AST) and lipid profiles are valuable tools for initial assessment and monitoring of hepatosteatosis.
- Specialized indices like the Fatty Liver Index (FLI), SteatoTest, and NAFLD Fibrosis Score can also be used to evaluate hepatosteatosis. According to the most recent and highest quality study 1, these non-invasive methods are increasingly preferred for initial assessment and monitoring of hepatosteatosis, as they prioritize morbidity, mortality, and quality of life by avoiding the risks associated with liver biopsy. The use of these non-invasive methods can improve patient outcomes and reduce the need for invasive procedures, making them a crucial part of hepatosteatosis evaluation and management.
From the Research
Evaluation of Hepatosteatosis
Besides liver biopsy, there are several non-invasive methods to evaluate hepatosteatosis, including:
- Ultrasound (US) 2, 3, 4: US can detect fat infiltration in the liver and is frequently used for screening, but it lacks specificity and sensitivity for diagnosing and monitoring therapy.
- Computed Tomography (CT) 2, 3, 4: CT can detect and quantify moderate to severe steatosis, but is inaccurate for diagnosing mild steatosis and involves radiation exposure.
- Magnetic Resonance Imaging (MRI) 2, 5, 3, 4: MRI, particularly proton-density fat fraction, is currently the most accurate and precise imaging biomarker to quantify liver steatosis.
- Elastography 3: Elastography can assess liver stiffness and detect fibrosis, which is often associated with hepatosteatosis.
- Spectroscopy 3: Spectroscopy can provide quantitative measurements of liver fat content.
- Quantitative ultrasound 4: Newer ultrasound techniques, such as quantitative ultrasound, show promise in turning qualitative assessment of steatosis into quantitative measurements.
- Dual-energy CT 4: Newer CT techniques, like dual-energy CT, show potential in expanding the role of CT in quantifying steatosis.
Advantages and Limitations
These non-invasive imaging modalities have several advantages, including:
- Reduced risk of morbidity and mortality compared to liver biopsy 5, 6
- Ability to provide quantitative measurements of liver fat content 5, 4
- Non-invasive and relatively low-cost 3 However, they also have some limitations, such as:
- Variability in sensitivity and specificity 3
- Limited availability and operating difficulty 3
- Need for further improvement and standardization 3