1 H-MRS对低级别和高级别脑胶质瘤鉴别诊断的作用及病理级别相关性的研究

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。资料与方法 搜集经临床手术、病理证实的脑胶质瘤36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Siemens Sonata 1．5T超导磁共振扫描仪，多体素扫描，点分辨表面线圈法，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。低级别、高级别脑胶质瘤的肿瘤组织分别和对侧正常脑组织的NAA／Cr、Cho／Cr、NAA／Cho比值存在非常显著性差异（P〈0．01）；低级别脑胶质瘤和高级别脑胶质瘤的肿瘤组织的NAA／Cr、Cho／Cr、NAA／Cho比值存在显著性差异（P〈0．05）。脑胶质瘤的NAA／Cho、Cho／Cr、NAA／Cr比值与病理级别相关，其中NAA／Cho和Cho／cr比值反映肿瘤级别较稳定；NAA／Cr、NAA／Cho比值存在负相关关系（相关系数rs分别为-0．663，-0．851），Cho／Cr比值存在正相关关系（相关系数rs为0．858）。结论 ^1H—MRS与MRI相结合能提高脑胶质瘤术前诊断的准确性。^1H-MRS可评价脑胶质瘤的分级，反映脑胶质瘤代谢特性以及肿瘤生长潜能。

Applications of 1 H-MRS in Differentiating and Grading of Gliomas and Its Correlation with pathology

Objective To evaluate the findings of ~1 H-MRS and clinical significance of ~1 H-MRS, and to explore the correlation between the findings of ~1 H-MRS and the pathological grading of gliomas.Materials and Methods 36 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 36 patients were underwent ~1 H-MRS before surgery on plain MRI scan. Muitiple voxel Proton magnetic resonance spectroscopy was performed on a 1.5T MR scanner using point resolved surface coil spectroscopy(PRESS),the variety of metabolite peaks were detected in different areas.Results The findings of ~1 H-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 ratios of NAA/Cr, Cho/Cr and NAA/Cho (P<0.01), Significant differences between Low grade gliomas and High grade gliomas were found in the ratios of NAA/Cr, Cho/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, Cho/Cr reflected pathologic grade of gliomas relatively steadily; there was significantly negative correlation in the ratios of NAA/Cr and NAA/ Cho(rs was -0.663, -0.851 respectively), and positive correlation in the ratios of Cho/Cr(rs was 0.858).Conclusion The combination of ~1 H-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.