阿尔茨海默病的高场氢质子磁共振波谱研究

Metabolic Changes in Patients with Alzheimer's Disease Assessed by High Field Proton Magnetic Resonance Spectroscopy

目的:探讨阿尔茨海默病(Alzheimer’s disease,AD)双侧海马的高场氢质子磁共振波谱(proton magnetic resonance spectroscopy,1H-MRS)的特点。方法:对AD组14例及正常对照组(normal control,NC)10例受试者行T1WI-3D薄层扫描并进行海马三平面MPR重建,在所得MPR图像上定位双侧海马。采用MRS测定双侧海马N-乙酰天门冬氨酸(N-acetyl aspartate,NAA)、胆碱(choline,Cho)、肌醇(myo-Inositol,mI)和谷氨酸-谷氨酰胺复合物(Glx)与肌酸(creatine,Cr)的比值。采用SPSS 17.0软件进行统计分析,观察AD组与NC组双侧海马各代谢物比值的差异。结果:AD组双侧海马的NAA/Cr、Glx/Cr比值较NC组降低,其差异具有统计学意义,AD组右侧海马mI/Cr比值较NC组升高具有统计学意义(P<0.05),左侧海马mI/Cr比值有升高趋势,但未达到统计学意义水平,AD组双侧海马Cho/Cr比值与NC组的差异无统计学意义。结论:双侧海马的高场MRS能够检测到AD特征性的代谢物改变。T1WI-3D扫描行海马三平面MPR重建有助于海马MRS的准确定位,提高图像质量及可信度。

Purpose：To investigate the metabolic changes of bilateral hipppocampi in patients with Alzheimer＇s disease（AD） by high field proton magnetic resonance spectroscopy（1H-MRS）.Methods： T1WI-3D scan and three dimensional MPR reconstruction of hippocampus were used in 14 patients with AD and 10 normal controls to ensure accurate positioning of bilateral hippocampi.1H-MRS was performed by PRESS sequence.Regions of interests were drawn in bilateral hippocampi to detect the NAA/Cr,Cho/Cr,Glx/Cr and mI/Cr ratios.Statistical analysis was performed by using SPSS for Windows（version 17.0）.Results：The bilateral NAA/Cr and Glx/Cr ratios of hippocampus in AD patients were significantly declined compared to that in normal controls（P0.05）.The bilateral mI/Cr ratios in AD patients were elevated compared to that in normal controls,but only the ratio of the right hippocampus showed a statistical significance（P0.05）.The Cho/Cr ratios in bilateral hippocampi showed no significant difference between the two groups.Conclusion：High field 1H-MRS of bilateral hippocampi can detect characteristic metabolic changes in AD patients.T1WI-3D scan and three dimensional reconstructions of hippocampus are helpful for accurate positioning of 1H-MRS,as a result,for improving image quality as well as reliability.