In-vivo study of quantitative ultrasound parameters in fatty rabbit livers

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease and can often lead to fibrosis, cirrhosis, cancer and complete liver failure. Liver biopsy is the current standard of care to quantify hepatic steatosis but it comes with increased patient risk and only samples a small portion of the liver. Imaging approaches to assess NAFLD include proton density fat fraction (PDFF) estimated via MRI and shear wave elastography. However, MRI is expensive and shear wave elastography is not sensitive to fat content of the liver. On the other hand, ultrasonic attenuation and the backscatter coefficient (BSC) have been observed to be sensitive to levels of fat in the liver. Ultrasound evaluation offers low risk to the patient and the ability to examine the majority of the liver, as compared to liver biopsy. Therefore, a need exists to further develop ultrasonic-based techniques to quantify hepatic steatosis. In this study we explored the use of attenuation and a principal component analysis (PCA) of the BSC to detect and quantify hepatic steatosis in vivo in a rabbit model of fatty liver.