中文摘要：

目的利用3T氢质子磁共振波谱（1H-MRS）研究轻微型肝性脑病（MHE）与无MHE的肝硬化患者后扣带回和基底节代谢的改变,并评价其与Child-Pugh评分、静脉血氨及神经心理测试之间的关系。方法对10例MHE患者、16例无MHE肝硬化患者和21例健康志愿者行后扣带回及右侧基底节单体素点分辨自旋回波波谱序列扫描。计算代谢物N-乙酰天门冬氨酸（NAA）、肌酐（Cr）、胆碱（Cho）、肌醇（mIns）、谷氨酰胺复合物（Glx）与Cr比值并进行三组间比较。所有研究对象在MRI检查前完成数字连接试验-A（NCT-A）、数字符号试验（DST）。所有患者在MR检查前后三天内进行了静脉血氨水平检测。结果在后扣带回,与正常对照组相比,MHE组和无MHE的肝硬化组的mIns/Cr（F=16.278,P〈0.001）及Cho/Cr（F=24.333,P〈0.001）都显著降低,Glx/Cr（F=0.908,P=0.411）有升高的趋势;与无MHE的肝硬化组相比,MHE组Cho/Cr进一步降低（P〈0.05）。在右侧基底节区,与正常对照组相比,MHE组和无MHE的肝硬化组的mIns/Cr（F=19.083,P〈0.001）显著降低,只有MHE组Glx/Cr（P〈0.05）显著升高,Cho/Cr（F=1.677,P〈0.199）有降低趋势;与无MHE的肝硬化组相比MHE组各代谢物的差别无统计学意义。Pear-son相关分析结果显示,仅右侧基底节的Cho/Cr与Child-pugh评分呈负相关（r=-0.444,P〈0.05）。结论肝硬化患者后扣带回及基底节区存在生化代谢的异常改变,且表现为区域不均质性,有MHE的肝硬化患者脑的生化代谢异常改变更加显著。后扣带回可作为检测肝硬化患者脑改变的一个敏感部位。

英文摘要：

Objective To study the cerebral metabolic alterations of the posterior cingulate cortex（PCC） and basal ganglia in cirrhotic patients with and without minimal hepatic encephalopathy（MHE） using 3 T magnetic resonance spectroscopy（MRS）,and to correlate the cerebral metabolic alterations with child-pugh scores,venous ammonia values and neuropsychiatric tests scores.Methods 1H-MRS（posterior cingulate cortex and basal ganglia） was performed using point-resolved echo spin spectroscopy（PRESS） sequences in 26 cirrhotic patients（10 MHE 16 non-MHE） and 21 healthy controls.Peak area of each metabolite,including NAA,Cr,Cho,mIns,Glx and their ratios to Cr were computed,then compared among the MHE,cirrhotic patients and healthy control groups with ANOVA tests.All subjects completed neuropsychological（NP） tests including number-connection test part A（NCT-A） and digital symbol test（DST） before magnetic resonance（MR） scanning.Venous ammonia was measured within 3 days before or after the MR scanning.Results In PCC,compared with the controls,both cirrhotic patients with and without MHE showed significantly decreased mIns/Cr（F=16.278,P0.001） and Cho/Cr（F=24.333,P0.001）,and the Cho/Cr of MHE was lower than that of patients without MHE.In basal ganglia,compared with the controls,both patient groups showed decreased mIns/Cr（F=19.083,P0.001）,and MHE patients showed increased Glx/Cr.Pearson correlation analysis displayed that there was a negative correlation between Cho/Cr（P0.05） of basal ganglia and Child-Pugh scores.Conclusion Patients with hepatic cirrhosis have the abnormal metabolic changes in the posterior cingulate cortex and basal ganglia with regional hetero-geneity and patients with MHE have more marked metabolite abnormalities than patients without MHE.The posterior cingulate cortex might be a sensitive location in detecting MHE.