脂肪肝单能CT定量诊断的实验研究

Single-energy CT Quantitative Diagnosis of Fatty Liver: An Experimental Study

目的 研究兔脂肪肝模型中肝脏脂肪含量与肝脏CT值之间的相互关系 ,为CT定量诊断脂肪肝提供理论依据。材料与方法 对造成不同程度脂肪肝的实验组 16只家兔和正常对照组 4只健康家兔分别行单能CT检查 ,测定肝脏的CT值。心脏穿刺取血 ,测定血清丙氨酸转氨酶 (ALT)、天门冬氨酸转氨酶 (AST)、碱性磷酸酶 (ALP)的水平。对肝脏进行组织学检查 ,用图像分析系统测量并计算肝脏脂滴占肝脏单位体积的百分比 (VP值 )。结果 实验组的VP值与CT值之间在统计学上有显著性意义的线性负向相关关系 (r =- 0 .90 ,t=7.5 4 ,P <0 .0 0 1) ;重度脂肪肝组血清ALT、AST、ALP水平较正常组、轻度脂肪肝组、中度脂肪肝组高 (P <0 .0 1)。结论 单能CT的肝脏CT值可以定量诊断脂肪肝的肝脏脂肪含量 ,判断脂肪肝的程度 ,效果优于血清ALT、AST。

Objective To explore the relation between fatty content of liver and CT attenuation in animal models, to provide theoretical basis for CT quantitative diagnosis of fatty liver.Materials and Methods Single energy CT scan was performed in 16 rabbits with fatty liver (experimental group) and in 4 healthy rabbits (control group). CT value of the liver was measured. Blood samples were obtained by puncture of the heart. Serum alanine transaminase (ALT), aspartase transamine (AST) and alkaline phosphatase (ALP) were estimated.Liver specimen was histologically examined. The percentage of the fatty content in liver (VP value) was estimated with image pattern analyzer.Results Significant linear negative correlation (r=-0.90, t=7.54, P<0.001) was found between VP value and CT attenuation value. Serum ALT, AST, and ALP in high grade fatty liver group were significantly higher than those in control group, light grade fatty liver group and moderate grade fatty liver group (P<0.01).Conclusion The amount and degree of liver fat can be assessed by estimating CT attenuation of the liver. This technique is superior to the estimation of serum ALT, AST and ALP in evaluating fatty liver.