磁共振波谱分析在颅脑胶质瘤分级中的应用研究

目的:分析脑胶质瘤的氢质子磁共振波谱(proton magnetic resonance spectroscopy,1H-MRS) 表现及其临床意义;探讨脑胶质瘤的1H-MRS 特点与其病理级别相关性.方法:搜集经临床手术、病理证实的脑胶质瘤病例49 例,按照WHO 诊断标准分成两组:低级别脑胶质瘤组、高级别脑胶质瘤组.所有患者在术前行1H-MRS 检查,均在MR 非增强成像的基础上获得.使用Philips Achieva 1.5T 超导磁共振扫描仪,单体素或多体素扫描,点分辨法,检测不同区域代谢物变化.结果:脑胶质瘤的1H-MRS 表现:肌酸(Cr) 轻度下降,N- 乙酰天门冬氨酸(NAA) 显著下降,胆碱(Cho) 显著增高.低、高级别脑胶质瘤的肿瘤组织与对侧正常脑组织的NAA、Cho、NAA/Cr、NAA/Cho 值存在显著性差异(P<0.05);低级别和高级别脑胶质瘤的肿瘤组织的NAA/Cr、NAA/Cho 值存在显著性差异(P<0.05).脑胶质瘤的NAA/Cho、Cho/Cr、NAA/Cr 值与病理级别相关,其中NAA/Cho和NAA/Cr 值反映肿瘤级别较稳定;NAA/Cr、NAA/Cho 值呈负相关关系,Cho/Cr 值呈正相关关系.结论:1H-MRS 结合MRI 能提高脑胶质瘤术前诊断的准确性.1H-MRS 能对胶质瘤进行分级,反映胶质瘤代谢特性以及肿瘤生长潜能.

The Applied Research of Magnetic Resonance Spectroscopy Imaging in the Classification of Cerebral Gliomas

Objective： To evaluate the findings of and clinical significance of 1H-MRS,and to explore the correlation between the findings of 1H-MRS and the pathological grading of gliomas.Methods： 49 patients of gliomas approved by pathology were reviewed,all cases were categorized into two groups（Low grade gliomas and High grade gliomas） according to WHO diagnostic criteria.The 49 patients were underwent 1H-MRS before surgery on plain MRI scan.Muitiple voxel and single voxel Proton magnetic resonance spectroscopy was performed on Philips Achieva 1.5T MR scanner,using point resolved spectroscopy（PRESS）,the variety of metabolite peaks were detected in different areas.Results： The findings of 1H-MRS： slightly decreased Cr,distinctly decreased NAA and distinctly increased Cho in gliomas.Significant differences between Low/high grade gliomas and normal tissue in contralateral brain hemispheres were found in the NAA,Cho,NAA/Cr and NAA/Cho（P0.05）,Significant differences between Low grade gliomas and High grade gliomas were found in the ratios of NAA/Cr and NAA/Cho（P0.05）.There was significant correlation between the ratios of NAA/Cr,Cho/Cr and NAA/Cho and the pathological grading of gliomas,and the ratios of NAA/ Cr,NAA/Cho reflected pathologic grade of gliomas relatively steadily;there was significantly negative correlation in the ratios of NAA/Cr and NAA/Cho,and positive correlation in the ratios of Cho/Cr.Conclusion： The combination of 1H-MRS and MRI improves preoperative diagnostic accuracy of gliomas,1H-MRS has made it possible to evaluate the grade of gliomas,obtain metabolic information of gliomas and reflect the potential growth of tumor.