脑单体素氢质子波谱扫描未抑制水分析的应用价值研究

Study of unsuppressed water analysis in single-voxel ~1H-spectroscopy in brain MRI

目的:通过比较两种拟合方法获得的代谢物参数,探讨未抑制水分析在脑单体素氢质子波谱扫描中的应用价值。方法:对20例行脑单体素氢质子波谱扫描的26组数据进行回顾性分析,每例分别进行常规脑部单体素短TE脚本拟合及未抑制水分析,并将第二种拟合获得的未抑制水参数作为第二分母,依次获得NAA、Cho、Cr等相关参数与其比值;比较两组数据拟合后获得的代谢物峰下面积、代谢物与Cr比值、相应代谢物与未抑制水比值,同时将相应拟合参数及比值进行统计学分析。结果:正常侧两种拟合方法获得的代谢物峰下面积、代谢物与Cr比值基本一致,差异无统计学意义(P>0.05),未抑制水拟合分析可提供Cr含量与水含量比值数据;患侧原始数据两种拟合获得的代谢物峰下面积、代谢物与Cr比值差异无统计学意义(P>0.05);与正常组织比较,患侧NAA与未抑制水比值、Cr与未抑制水比值、NAA与Cr比值差异有统计学意义(P<0.05)。结论:未抑制水分析拟合在氢质子单体素波谱扫描中可提供代谢物相对于水含量的半定量数据,可以直接显示匀场质量,方便拟合参数调整;且在常规拟合中出现代谢物与Cr比值异常时可进一步明确相应代谢物各自的变化,对涉及Cr代谢改变病变的定性诊断有重要意义。

Objective： To study the application value of unsuppressed-water fitting analysis in brain single-voxel spectroscopy by comparing the parameters obtained from the two fitting scripts with the proton spectroscopy of the brain. Methods： 20 patients were recruited in this study and received MRS scan. Two groups of data derived from the conventional brain single voxel short TE script fitting and unsuppressed-water fitting analysis in each patient. The second fitting was non-water-suppression as the second denominator. A total of 26 sets of data were analyzed. NAA,Cr,Cho and Lac related pa- rameters and the ratio were obtained in order. Metabolite area under peaks, metabolite-to-Cr ratios, ra- tios between water-suppression and unsuppressed water fitting were compared. Paired t test was used to compare the fitting parameters and the ratio between the suffering sides. Results：The original data of metabolite area under peaks,metabolites-to-Cr ratios obtained in the normal side by the two fitting methods are basically the same,there was no significant differences found （P〉0.05）. Meanwhile, the above parameters in the suffering side had no significant difference （P〉0.05） either. But when compared with the normal tissue, significant difference was found in Lac,Cr,Lac to Cr ratios between wa- ter-suppression and unsuppressed water fitting （P〈0.05）. Conclusion： Unsuppressed water analysis fitting in 1 H proton single-voxel spectroscopy scan can provide semi-quantitative analysis of metabolite related to water content, it can directly display the shimming quality, and facilitate adjustment of fitting parameter. It has great significance in the qualitative diagnosis of Cr metabolism-related changes and abnormal metabolite-to-Cr ratios by providing further clear changes of each metabolite in conventional fitting.