探讨联合应用MRS和DWI在脑胶质瘤分级中的诊断价值

Evaluation of Combination Use of ^1H-MRS and DWI in Grading Cerebral Gliomas

目的探讨联合应用氢质子磁共振波谱（1H-MRS）相关代谢物和磁共振扩散加权成像（DWI）的表观扩散系数（ADC）值在脑胶质瘤分级诊断中的诊断价值。方法回顾性分析经病理证实的59例脑胶质瘤的MRS和DWI图像。按照WHO 2007标准,将病例分为两组：低级别胶质瘤组（Ⅰ-Ⅱ级,24例）和高级别胶质瘤组（Ⅲ-Ⅳ级,35例）,测量并计算肿瘤实质区、健侧脑组织区代谢物及ADC值的相对值和比值,作统计学分析。结果在59例脑胶质瘤中,r NAA、Cho/Cr、NAA/Cr、NAA/Cho及r ADC在低、高级别组胶质瘤比较中差异均有统计学意义（P〈0.05）,而r Cho和r Cr在两组胶质瘤比较中差异无统计学意义（P〉0.05）;经受试者工作特征曲线分析发现r NAA、NAA/Cr、NAA/Cho、r ADC鉴别胶质瘤分级的曲线下面积〉0.5,MRS＋r ADC鉴别胶质瘤分级的曲线下面积（0.956）〉单独运用MRS（0.893）或r ADC的曲线下面积（0.805）,MRS＋r ADC诊断低、高级别胶质瘤的敏感性和特异性分别达88.6%、95.8%。结论联合分析MRS参数（r NAA、NAA/Cr、NAA/Cho）和DWI参数（r ADC）对诊断胶质瘤分级具有较高的敏感性和特异性,可为临床治疗方案的制定及判断预后提供帮助。

Objective To investigate the value of ^1H-magnetic resonance spectroscopy（1H-MRS） metabolites and apparent diffusion coefficient（ ADC） of diffusion-weighted imaging（ DWI） in grading the cerebral gliomas. Methods1 HMRS and DWI imaging of total 59 patients with pathologically-proved gliomas were retrospectively analyzed. According to the 2007 World Health Organization（ WHO） standards,the patients were divided into low-grade glioma group（ grade Ⅰ-Ⅱ,n = 24） and high-grade glioma group（ grade Ⅲ- Ⅳ,n = 35）. The values of metabolites and ADC of the tumor parenchyma and corresponding contralateral tissue area were measured and calculated respectively,the results were statistically analyzed. Results In the 59 patients with glioma,statistically significant differences in rN AA,Cho / Cr,NAA / Cho and rA DC existed between the low-grade glioma group and the high-grade glioma group（ P〈0. 05）,while the differences in rC ho and rC r between the two groups were not statistically significant（ P〉0. 05）. ROC analysis showed that the area under curve（ AUC） of rN AA,NAA / Cr,NAA / Cho and rA DC in differentiating glioma grades was larger than 0. 5,while AUC of MRS plus rA DC combination was 0. 956,which was larger than that of simple MRS（ 0. 893） as well as that of simple rA DC（ 0. 805）. The diagnostic sensitivity and specificity of MRS plus rA DC combination in diagnosing low-grade and high-grade gliomas were 88. 6% and 95. 8% respectively. Conclusion The results of this study indicate that combination analysis of MRS parameters（ rN AA,NAA / Cr and NAA / Cho） and DWI parameter（ rA DC） have higher sensitivity and specificity in grading gliomas,which is very helpful in making clinical treatment plan and in judging the prognosis.