单体素~1H-MRS分析在评估脑胶质瘤放疗效果中的应用研究

Application of ~1H-MRS in Evaluating the Value of Radiotherapy Effect on Brain Gliomas

目的探讨单体素氢质子磁共振波谱(1H-MRS)分析在评估脑胶质瘤放疗效果中的应用价值。资料与方法对28例Ⅱ～Ⅳ级脑胶质瘤术后患者于放疗前及放疗后1～2个月行MRI增强检查及1H-MRS检查,测定各主要代谢产物峰下面积,并计算出病灶波谱参数胆碱(Cho)/肌酸(Cr)、Cho/N-乙酰天门冬氨酸(NAA)、NAA/Cr比值及脂质(Lip)波、乳酸(Lac)波出现概率。以放疗后5～10个月MRI增强扫描结果及二次手术结果为随访标准进行分组,即放疗后抑制组、放疗后复发组及放射性脑损伤组,对各组放疗前后的波谱参数进行对照,验证1H-MRS参数与放疗效果的相关性。结果肿瘤抑制组表现为Cho浓度及Cho/Cr、Cho/NAA比值显著降低(P<0.05),NAA、Cr浓度有所下降,Lip-Lac波出现增多。肿瘤复发组Cho浓度及Cho/Cr、Cho/NAA比值仍显著升高,Cr浓度中度升高,出现更多的Lip-Lac波,仍表现为特征性肿瘤波谱。放射性脑损伤组Cho/Cr、Cho/NAA比值较放疗前轻度上升,远不及复发组上升明显,NAA及Cr浓度下降。结论单体素1H-MRS能从代谢方面无创伤地监测脑胶质瘤放疗后的组织代谢、生理生化改变,具有早期评价胶质瘤放疗疗效的优越性。

Objective To discuss the clinic value of 1↑H MRS on radiotherapy effect of brain gliomas.Materials and Methods 28 cases of glioma with pathological grade Ⅱ-Ⅳ after surgercal operations received contrast MRI and 1↑H MRS examinations before and after radiotherapy 1-2 month to measure under-peak area of main metabolites and calculate the lesion′s parameters of MRS：Cho/Cr、Cho/NAA、NAA/Cr ratio and Lip-Lac appear probability.According to contrast MRI features after radiotherapy 5-10 months and the second operations results,we divided the patients into post-radiotherapy restrained group,recurrence group and radiation-induced brain injury group in order to compare MRS parameters of different groups and verify the relativity between MRS parameters and radiotherapy effect.Results The 1↑H-MRS performance of restrain group showed notably lower ratio of Cho/Cr、Cho/NAA and Cho density.NAA and Cr density lightly decreased.More Lip Lac wave emerged.While recurrence group showed higher ratio of Cho/Cr,Cho/NAA ratio and Cho density notably increased,Cr density morderately increased.Lip Lac wave appeared more,which indicated characteristic MRS of tumor.Radiation-induced brain injury group showed Cho/Cr,Cho/NAA ratio gently rised,far from recurrence group.Conclusion 1H-MRS can noninvasively monitor tissue metabolism,biochemistry change and physiological change of gliomas after radiotherapy,it has advantage of early evaluating radiotherapy effect on brain gliomas.