慢性肝硬化脑代谢异常的磁共振质子波谱研究

1H MRS study of brain metabolic disorder in patients with chronic liver cirrhosis

目的用磁共振质子波谱的方法研究慢性肝硬化所致的脑代谢异常，从而更好地理解肝性脑病的病理生理机制，为临床诊断和治疗提供客观依据。方法在２．０Ｔ的场强条件下，对３０例慢性肝硬化患者（代偿期９例、失代偿期１１例、慢性肝性脑病１０例）和１５名健康志愿者的脑组织进行了质子波谱［采用激励回波获得方式（ＳＴＥＡＭ）序列］和ＭＲＩ检查。测量质子波谱中所观察到的代谢产物的峰高，以总肌酸（Ｃｒ）为参照计算峰高的比值，进行相对定量分析。并对代谢产物的变化之间及与ＭＲＩ信号改变之间的关系进行相关性分析。结果在脑病组和失代偿期组中，肌醇（ｍＩ）／Ｃｒ、含胆碱化合物（Ｃｈｏ）／Ｃｒ的平均值均低于健康对照组和代偿期组，而谷氨酸谷氨酰胺复合物（Ｇｌｘα）／Ｃｒ值则升高（Ｐ＜０．０５）。脑病组Ｇｌｘα／Ｃｒ值又高于失代偿期组（Ｐ＜０．０１），但ｍＩ／Ｃｒ、Ｃｈｏ／Ｃｒ值在两组之间无显著性差异（Ｐ＞０．０５）。上述比值在对照组与代偿期组之间无显著性差异（Ｐ＞０．０５）。ｍＩ／Ｃｒ与Ｇｌｘα／Ｃｒ值之间呈负相关（ｒ＝－０．５１，ｎ＝４４，Ｐ＜０．００１）。在脑病组和失代偿期组中，Ｔ１ＷＩ上苍白球信号明显升高（Ｐ＜０．０５），且信号变化与?

Objective To study the metabolic alterations in the brain of patients with chronic liver cirrhosis with 1H magnetic resonance spectroscopy( 1H MRS) for better understanding the pathophysiology of chronic hepatic encephalopathy (CHE), which will help us in the diagnosis and treatment of this disease. Methods STEAM 1H MRS and MRI were performed in 30 patients with chronic liver cirrhos is and 15 healthy volunteers. The height of resonance peaks of different metabolites was measured and the ratios of the other metabolites to Cr were calculated. We also studied the correlation between metabolites and the association between globus pallidus signal intensity and the spectroscopic alterations. Results In patients with severe cirrhosis (in decompensatory period) or CHE, the mean values of mI/Cr and Cho/Cr ratio were significantly lower than those in healthy volunteers or patients with minor cirrhosis(in compensatory period) ( P <0.05),but the mean value of Glx α/Cr ratio was significantly higher( P <0.05).The Glx α/Cr ratio in patients with CHE was higher than that in patients with severe cirrhosis ( P <0.01).There were no significant differences of these ratios between healthy volunteers and patients with minor cirrhosis( P >0.05).There was negative correlation between mI/Cr and Glx α/Cr( r = -0.51, n =44, P <0.001). On T 1 weighted images, the globus pallidus signal intensity was significantly higher in patients with severe cirrhosis or CHE. mI/Cr、Cho/Cr、and Glx α/Cr correlated significantly with MRI signal changes respectively. Conclusions Proton MRS can demonstrate brain metabolic changes in patients with chronic liver cirrhosis in vivo noninvasively, thereby helping interpret the pathophysiology of CHE.