影像学技术定量诊断脂肪肝的实验研究

目的 利用ROC曲线比较生化、超声、CT、质子磁共振波谱(1H MRS)定量诊断脂肪肝的应用价值.方法 选用45只健康新西兰大白兔,高脂高糖饲料加酒精饮料建立不同程度脂肪肝模型,应用生化、超声、CT及1H MRS多种.临床诊断方法,共观测18个变量指标,在每种诊断方法所观测的指标中,选取与脂肪肝分级相关性最高的指标,并以此进行受试者操作特征(ROC)曲线分析和ROC曲线下面积Z检验,比较这几种诊断方法的应用价值.结果 在所有18个观测指标中,血清胆固醇、超声衰减系数、肝CT值和1H MRS脂肪波峰下面积分别是生化、超声、CT、1H MRS诊断方法中与脂肪肝分级相关性最高的观测指标,相关系数分别为0.886(P=0.000)、0.483(P=0.002)、-0.764(P=0.000)、0.558(P=0.001);ROC曲线分析和Z检验显示:上述各指标ROC曲线下面积分别为0.981,0.581,0.810,0.713,除1H MRS脂肪波峰下面积与超声衰减系数、肝CT值之间差异无统计学意义外(P>O.05),其他两两之间差异均有统计学意义(P1H MRS>超声;生化测定血清胆固醇水平对判断脂肪肝程度可能具有重要的意义,值得进一步研究.

An experimental study of quantitative diagnosis of fatty liver by imaging technology

Objective To compare the values of biochemistry, ultrasonography ( US) , computed tomography(CT) and proton magnetic resonance spectroscopy ('H MRS) in the quantitative diagnosis of fatty liver. Methods Forty-five healthy New Zealand rabbits were enrolled in the study. Hepatic steatosis models were established by giving high fat, high sugar diet with drinking water containing five percent ethanol. Eighteen variable indexes were measured by biochemical examination, US,CT and ' H MRS. ROC analysis and Z test were used to compare the diagnostic efficacy of different clinical examinations. Results Among eighteen variable indexes,serum TC,ultrasound attenuation coefficient,liver CT value and ' H MRS fat peak area had the highest degree of relationship by biochemical examination, US, CT, ' H MRS in diagnosis of fatty liver, correlation coefficients were 0.886,0.483, -0. 764, 0. 558, and areas under curve were 0. 981, 0. 581, 0. 810, 0. 713, respectively. There were significant differences in areas under curve between every two groups except 'H MRS fat peak area and ultrasound attenuation coefficient, liver CT value. Conclusions The diagnostic values of imaging modalities in the hepatic steatosis grade, their order is CT >'H MRS> US; Serum TC maybe have important diagnostic value in evaluating hepatic steatosis grade,this is very worth further studying.