CT灌注成像评价兔肝不同程度热缺血再灌注损伤的研究

Value of CT perfusion in different degrees of hepatic warm ischemia-reperfusion injury of rabbits

目的探讨应用CT灌注成像评价兔肝热缺血再灌注损伤时各参数的变化规律及其与肝脏酶学指标的相关性。方法新西兰大白兔30只，随机数字表法均分成3组（W0、W1、W2组）。W1和W2组分别制作为热缺血时间为40和60min的热缺血再灌注损伤模型，W0为对照组。各组行全肝CT灌注成像，测量肝动脉灌注指数（PI）、肝动脉灌注量（AF）和门静脉灌注量（PF）。取耳缘静脉血检测血清天冬氨酸转氨酶（AsT）、丙氨酸转移酶（ALT）及乳酸脱氢酶（I。DH）；取冻存肝组织检测超氧化物歧化酶（SOD）、丙二醛（MDA）及髓过氧化物酶（MPO）。结果梗死区中，W0与W2组问AF的差异无统计学意义（P〉0．05），w1与W2组问PF的差异无统计学意义（P〉0．05），余W0、Wl、W2组间PI、AF、PF的差异均有统计学意义（P〈0．05）；PI、PF与各肝酶指标存在相关关系，AF与各肝酶指标不相关。非梗死区中，W1与W2组间PI、AF的差异无统计学意义（P〉0．05），W0与w2组间PF的差异无统计学意义（P〉0．05），余W0、w1、W2组问PI、AF、PF的差异均有统计学意义（P〈（）．05）；PI、AF与各肝酶指标存在相关关系，PF与各肝酶指标不相关。评价不同热缺血程度梗死区时，PI、PF有较高诊断效能（PI的曲线下面积=0．965，AF的曲线下面积=0．736，PF的曲线下面积=1．00）；评价不同热缺血程度非梗死区时，PI、AF有较高诊断效能（PI的曲线下面积=0．938，AF的曲线下面积=0．993，PF的曲线下面积=0．618）。结论CT灌注成像可以动态监测热缺血再灌注损伤后的血流动力学改变，可以作为肝酶学指标等评估肝脏损伤程度的很好补充。

Objective To prospectively investigate the changes of hepatic CT perfusion parameters and the correlation with serum amylase （AST, ALT, LDH, SOD, MAD and MPO） in rabbits hepatic warm ischemia-reperfusion injury （WIRI） models undergoing different warm ischemia time. Methods New Zealand rabbits underwent 4{） rain and 60 rain of right posterior lobe ischemia followed by 6 h reperfusion （n = 10 each）, named as Wl, W2 groups respectively. Ten rabbits served as normal controls （W0）. All the rabbits were given CT perfusion protocol The perfusion indices of arterial flow （AF）, portal flow （PF）, and perfusion index （PI） were measured after obtaining perfusion index maps on the workstation. Blood samples were taken from the rabbit ear vein to measure the levels of ALT, AST, and LDH. The contents of SK）D, MDA and MPO in liver tissues were determined, and histopathological changes were examined. Results Significant differences were found between the group W0, Wl and W2 in the infarcted areas and non- infarcted areas by PI and AF and PF （P〈0. 05）, except that in the infarcted areas the AF value betwween the group W0 and W2, the PF value between the group Wl and W2 had no statistical difference, and in the non- infarcted areas the difference of the PI and AF value betwween the group Wl and W2, the PF value between the group W0 and W2 was not significant eihter. In the infracted area, P1 and PF of WlRI groups positively correlated with biochemical parameters. AF was not correlated with biochemical parameters. In the non- infracted area, PI,AF was correlated with biochemical parameters, PF was not correlated with biochemical parameters. The PI and PF value could efficiently diagnose rabbit hepatic WlRI in the infarcted area （for PI, AR and PR, AUC= 0. 965, 0. 736 and 1.00 respectively）, and PI and AF value could efficiently diagnose rabbit hepatic WlRI in the non- infarcted area （for PI, AF and PF, AUC = 0. 938, 0. 993 and 0. 618 respectively）. Conclusion CT perfusion can dynamically monitor the hemodynamic changes after WIRI and may suggest potential microcirculatory disturbances.