磁共振波谱成像技术对评价早期肝性脑病严重程度的可行性分析

摘要

目的 运用3.0 T磁共振波谱成像技术评估早期肝性脑病(minimal hepatic encephalopathy,MHE)患者的局部脑代谢改变.材料与方法 收集30例伴有轻微肝性脑病的肝硬化患者,29例不伴有轻微肝性脑病的肝硬化患者及30名健康志愿者.在3.0 T场强下对大脑前扣带回及基底节区进行扫描得到其单体素质子波谱成像的数据.利用LC-model软件计算出N-乙酰天门冬氨酸(N-acetylaspartate,NAA)、肌醇(myo-inositol,MI)、谷氨酸(glutamic,Glu)、谷氨酰胺(glutamate,Gln)以及肌酸(creatine,Cr)的浓度,并对其进行分析比较3组患者之间的差异.结果 肝硬化患者的Glu浓度显著升高,在合并MHE的肝硬化患者中尤其明显.在所有肝硬化患者及对照组中,仅有部分肝硬化患者的Gln浓度升高.肝硬化患者的MI浓度明显降低,但两组肝硬化患者降低的程度差异无统计学意义.3组患者的NAA浓度差异无统计学意义.结论 3.0 T场强下的磁共振波谱成像(magnetic resonance spectroscopy,MRS)扫描可以检测出合并MHE肝硬化患者的脑代谢改变.合并轻微肝性脑病的肝硬化患者的Glu浓度增高.Glu浓度可以作为评价合并轻微肝性脑病的肝硬化患者病情严重程度的敏感指标.%Objective: To evaluate regional cerebral metabolic changes in minimal hepatic encephalopathy (MHE) patients using magnetic resonance spectroscopy (MRS) in 3.0 T scanner. Materials and Methods: This study comprised 30 cirrhotic patients with MHE, 29 cirrhotic patients without MHE and 30 healthy volunteers. Single-voxel proton MRS data in the anterior cingulate cortex (ACC) and basal ganglia were acquired using a 3.0 T scanner. The concentrations of N-acetylaspartate (NAA), myo-inositol (MI), glutamate (Glu), glutamine (Gln) and creatine (Cr) were obtained by LC-model software. Statistical analysis was performed to evaluate the differences between the three groups. Results: There was a significant increase in Glu for the cirrhotic patients, particularly the MHE patients. There was an elevation of Gln in the cirrhotic patients, but not in all cirrhotic patients or controls. There was a significant decrease in MI for the cirrhotic patients, but no significant difference between the two cirrhosis groups. There was no significant difference in NAA between the three groups. Conclusion: MRS using a 3.0 T MR scanner could detect cerebral metabolic changes in cirrhotic patients with MHE. Glu levels were elevated in cirrhotic patients with MHE; Glu levels could be used as a sensitive indicator to evaluate the severity of MHE in patients with cirrhosis.