Liver microcirculation after hepatic artery embolization with degradable starch microspheres in vivo

AIM： To observe the dynamic changes of liver microcirculation in vivo after arterial embolization with degradable starch microspheres （DSM）. METHODS： DSM were injected into the proper hepatic artery through a silastic tube inserted retrogradely in gastroduodenal artery （GDA） of SD rats. Fluorescent microscopy was used to evaluate the dynamic changes of blood flow through the terminal portal venules （TPVs）, sinusoids and terminal hepatic venules （THVs）. The movements of DSM debris were also recorded. Six hours after injection of DSM, percentages of THVs with completely stagnant blood flow were recorded. RESULTS： Two phases of blood flow change were recorded. In phase one： after intra-arterial injection of DSM, slow or stagnant blood flow was immediately recorded in TPVs, sinusoids and THVs. This change was reversible, and blood flow resumed completely. In phase two： after phase one, blood flow in TPVs changed again and three patterns of blood flow were recorded. Six hours after DSM injection, 36.9% ± 9.2% of THVs were found with completely stagnant blood flow. CONCLUSION： DSM can stop the microcirculatory blood flow in some areas of liver parenchyma. Liver parenchyma supplied by arteries with larger A-P shunt is considered at a higher risk of total microcirculatory blood stagnation after injection of DSM through hepatic artery.

Contrast-enhanced ultrasound evaluation of hepatic microvascular changes in liver diseases

AIM： To assess if software assisted-contrast-enhanced ultrasonography （CEUS） provides reproducible perfu- sion parameters of hepatic parenchyma in patients af- fected by chronic liver disease. METHODS： Forty patients with chronic viral liver dis- ease, with （n = 20） or without （n = 20） cirrhosis, and 10 healthy subjects underwent CEUS and video re- cordings of each examination were then analysed with Esaote＇s Qontrast software. CEUS dedicated software Qontrast was used to determine peak （the maximum signal intensity）, time to peak （TTP）, region of blood value （RBV） proportional to the area under the time- intensity curve, mean transit time （MTT） measured in seconds and region of blood flow （RBF）. RESULTS： Qontrast-assisted CEUS parameters dis- played high inter-observer reproducibility （κ： coefficients of 0.87 for MTT and 0.90 TTP）. When the region of in-terest included a main hepatic vein, Qontrast-calculated TTP was significantly shorter in cirrhotic patients （vs non-cirrhotics and healthy subjects） （71.0 ± 11.3 s vs 82.4±15.6 s, 86.3±20.3 s, P 〈 0.05）. MTIs in the patients with liver cirrhosis were significantly shorter than those of controls （111.9±22.0 s vs 139.4±39.8 s, P 〈 0.05）, but there was no significant difference between the cirrhotic and non-cirrhotic groups （111.9± 22.0 s vs 110.3 ±14.6 s）. Peak enhancement in the patients with liver cirrhosis was also higher than that observed in controls （23.9± 5.9 vs 18.9±7.1, P = 0.05）. There were no significant intergroup differences in the RBVs and RBFs. CONCLUSION： Qontrast-assisted CEUS revealed re- producible differences in liver perfusion parameters during the development of hepatic fibrogenesis.

Hepatic microcirculatory disturbances in patients with chronic hepatitis B

Objective To document morphological changes in hepatic microcirculation in liver tissue with hepatitis B and the pathogenesis of hepatic microcirculatory disturbances.Methods Liver tissue samples were obtained from patients with hepatitis B by liver biopsy. These samples were examined with a light microscope and transmission electron microscope. Results Hepatic microcirculatory disturbances existed in patients with hepatitis B, including those with normal liver function, manifested by red blood cell aggregation in sinusoids seen under light microscope and sinusoidal capillarization seen under electron microscope. Weibel-Palade bodies in sinusoidal endothelial cells were seen in 26 out of 53 cases. Intimate contacts were found between lymphocyte/Kupffer cells and sinusoidal endothelial cells. Conclusions Hepatic microcirculatory disturbances exist in patients with hepatitis B .The appearance of Weibel-Palade bodies in sinusoidal endothelial cells may be a key step in the development of hepatic microcirculatory disturbances.