| Background:The chronic inflammation and necrosis of liver parenchyma caused by any kind of pathogeny can arouse durative hyperplasia of fibril connective tissue, once the hyperplasia exceeds the degradation liver fibrosis will occur. The diffuse liver fibrosis consorting with destruction of hepatic lobules can cause liver cirrhosis. Both of them are continuous process, which can't be separated exactly. Liver fibrosis and early cirrhosis are the reversible phase of chronic hepatic diseases, so it's of great significance to diagnose and treat them as early as possible. At present, the diagnosis mostly depends on the medical history﹑blood test and echography , but liver's compensating function is so strong that early clinical representation and hepatic function are mostly normal. The two-dimensional imaging of liver parenchyma can show the main pathological changes of the metaphase and late liver cirrhosis, but examiner can influence it subjectively and there is scarce quantitative method. Color Doppler flow imaging (CDFI) has important referenced value, but it's short of peculiarity. Although the biopsy of liver tissue is the "gold standard", it is not accepted widely for the trauma caused by the operation. The development of the contrast ultrasound makes it possible to evaluate the blood perfusion of liver and the alternation of microcirculation quantitatively for the contrast agent is a good tracer of blood circulation , which provides a new way to diagnose liver fibrosis and cirrhosis. It's reported that the mean transit time (MTT) of the contrast agent can serve as a diagnostic index, though the reason is in discussion. Computer-assisted texture analysis is a new margin subject, which is seeping in many fields including ultrasound imaging. Studies were made to seek the possibility to evaluate the echo-texture of parenchymal organs quantitatively, the results of which proved that the changes of echo-texture can reflect the changes of hepatic structure. But there is yet no unified standard to choose methods and parameters to analyze texture at present. Objective:To investigate the feasibility of the diagnosis of liver fibrosis and cirrhosis by measuring the time of contrast agent overpassing the liver and time-intensity curve (TIC) of liver parenchyma after intravenously injecting self-made albumin perfluorocarbon ultrasonic contrast agent. If the changes of echo-texture measured by neighborhood-pixels algorithm can reflect the pathological state of liver fibrosis and cirrhosis and the role of SonoCT in improving its ability of texture analysis are also investigated.Methods:There were 80 rats involved in this study, which were divided into 5 groups, and each one had 16 rats. The model of liver cirrhosis was established in 4 groups by injecting pure CCI4 at the first time, 50% CCI4 anon twice a week, 20% alcohol as the only drink and high cholesterol diet for 6 weeks﹑8 weeks﹑10 weeks and 12weeks respectively, and the other one was a control.After intravenously injecting self-made albumin perfluorocarbon ultrasonic contrast agent (UCA), the time of the agent transit liver in all groups was measured. The appearing times of the contrast agent in inferior vena cava and hepatic vein and the compensated time of the contrast agent in hepatic vein (the time of contrast agent transiting liver viz the difference between the former times) were observed. The time-intensity curve of liver parenchyma was established after intravenous contrast ultrasound to evaluated the changes of hepatic blood perfusion in different phases of liver fibrosis and cirrhosis. The real time images were recorded for 2 minutes after injecting UCA, and video frequency analysis was taken to contrast the changes of liver's gray scale before and after ICU. Parameters such as peak intensity (PI), time to peak (TP), half time of descent (HT), descending slope (DS), area under the curve (AUC) and mean transit time (MTT) were measured.Neighborhood-pixels algorithm was used to analyze the hepatic echo textures in liver fibrosis and...
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