轻微型肝性脑病的DTI定量研究  

Quantitative Study of Changes of Brain in Patients having Cirrhosis Complicated with Mild Hepatic Encephalopathy by Diffusion Tensor Imaging

作　　者：彭君[1] 刘鹏飞[1] 

机构地区：[1]哈尔滨医科大学附属第一医院磁共振科,哈尔滨150001

出　　处：《放射学实践》2009年第9期986-989,共4页Radiologic Practice

摘　　要：目的:利用扩散张量成像(DTI)评价有与没有轻微型肝性脑病(MHE)的肝硬化患者是否存在异常脑改变,并探讨其在检测MHE中的价值。方法:29例肝硬化患者进行MRI与DTI扫描,其中15例有MHE,经神经心理学测试的数字连接试验(NCT-A)及数字符号试验(DST)测试。14例健康志愿者作对照。DTI选用平均扩散率(MD)及各向异性分数(FA)作为参数,选取主要的白质及深部灰质共7个部位为感兴趣区,计算各部位MD及FA值。结果:有与没有MHE的肝硬化患者及对照组不同部位MD值间差异有统计学意义(P<0.05);FA值无显著性差异(P>0.05)。分别与对照组比较,MHE组在5个部位MD值显著性增加(P<0.05);肝硬化组仅在尾状核部MD值显著增加(P<0.05)。结论:MHE患者出现MD值增高不伴FA值异常改变,提示存在轻度细胞外间隙脑水肿,没有脑白质微细结构的变化。在临床及神经心理学测试之前出现MD值变化表明DTI在检测MHE中有一定价值。Objective：To evaluate the quantitative changes of brain in patients having cirrhosis complicated with mild hepatic encephalopathy（MHE） by diffusion tensor imaging（DTI）,and to study the value of DTI in detecting MHE.Methods：MRI and DTI were performed in 29 patients with cirrhosis.Of them,15 patients had MHE diagnosed according to the results of number connection test A（NCT A） and digital symbol test（DST）,the others had no MHE.14 healthy volunteers as controls had the same examinations undertaken.Fractional anisotropy（FA） and mean diffusivity（MD） were used as DTI parameters.Totally seven regions including main white matter and deep gray matter in both cerebral hemispheres were chosen as regions of interest（ROI）.The MD and FA values of these various regions in different groups were calculated and compared.Results：The MD values of various regions in different groups had significant statistic differences（P〈0.05）,no significant statistic differences were showed in FA among these different groups（P〉0.05）.Compared with control group,significantly increased MD values were found in five cerebral regions in MHE patients（P〈0.05）;In patients with cirrhosis but no HE,increase MD value was only showed in caudate nucleus（P〈0.05）.Conclusion：Increased MD values were showed in MHE patients,yet with no abnormal change of FA value,which indicating mild extra-cellular cerebral edema was existed but with no micro-structural changes of cerebral white matter.MD value changes existed before clinical and neuro-psycological abnormalities suggested that DTI plays an significant role in detecting MHE.

关 键 词：肝硬化 肝性脑病 磁共振成像 扩散张量成像 

分 类 号：R747.9[医药卫生—神经病学与精神病学] R445.2[医药卫生—临床医学]