Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. The noninvasive and accurate classification of NAFLD is still a challenging problem. In this study we pro- posed a new quantitative ultrasound (QUS) technique, which combined multiple QUS parameters for distinguishing steatosis stages. NAFLD was induced in the livers of 57 rats by gavage feeding with a high fat emulsion, while 8 rats were given a standard diet to serve as controls. Ex vivo ultrasound mea- surement was conducted for capturing the radiofrequency signal. Six QUS parameters were extracted and selected for linear combination. The results show that the overall performance of the combined parameter is better than that of the single QUS parameter. The accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC) while using our proposed method to distinguish mild steatosis (stage S1) from the steatosis under stage S0 are 90.1%, 0.93, 0.88 and 0.97 respectively. In conclusion, the proposed method in this study can make up for the deficiency of single parameter and improve the quantitative staging ability of fatty liver, and thus could play an important role in the diagnosis of NAFLD.
Keywords: NAFLD; characteristic parameters; fusion; quantitative analysis; steatosis stage.