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止常脑组织的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MKI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 t H -MRS , and to explore the correlation between the findings of t H - 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 I H -MRS before surgery on plain MRI scan. Multiple 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（P 〈 0.05 ） , Sig- nificant differences between Low grade gliomas and High grade gliomas were found in the ratios of NAA/Cr and NAA/Cho（ P 〈 0.05 ）. 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 rela- tively 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, 1 H - MRS has made it possible to evaluate the grade of gliomas , obtain metabolic information of gliomas and reflect the potential growth of tumor.