Abstract. Portal vein hypertension generally occurs in liver diseases like hepatic cirrhosis. It causes hemodynamic changes that are closely related to liver disease. At advanced stages of hepatic cirrhosis, portal vein hypertension leads to the atrophy of the right lobe of the liver and the hypertrophy of the left lobe through a process that has not yet been fully explained. Based on the hemodynamic changes that are known to occur, we hypothesize that liver volume is related to the distribution of blood flowing from the splenic vein (SV) that carries hepatotrophic factors from the spleen and pancreas. We studied blood flow in the portal vein system to validate this hypothesis through in vitro experimentation and a computational fluid dynamics (CFD) analysis involving both simplified and patient-specific models based on four healthy subjects and two patients with liver cirrhosis. The results confirmed the hypothesis that right-lobe atrophy is significantly influenced by the distribution of blood from the SV. Moreover, the patients with liver cirrhosis had a significantly larger mass fraction of spleen-derived blood in the left portal vein branch (LPV) than healthy subjects, a result consistent with right-lobe atrophy and left-lobe hypertrophy.

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Speckle simulation is a powerful protocol to investigate the properties of speckle and evaluate image processing method. However, only static speckle images can be simulated by available methods without considering time-integrated effect of CCD. A time–integrated dynamic speckle simulation method basedon coherent imaging was developed. Through the new simulation method, the effect of speckle size on LSCI was investigated. The smaller the speckle size is, the higher the spatial resolution become.But the one-dimensional speckle size should exceed two pixels to sample the speckle pattern. The characteristics of existing speckle contrast imaging methods were studied based on spatial statistics, and optimal parameters are given to obtain accurate and less noisy image. In general, the new simulation method for laser speckle imaging is a powerful tool to monitor blood flow in vivo and lay a solid foundation for the study of hemodynamics.