氢质子磁共振波谱检测脑胶质瘤放疗后的放射性脑损伤

Detection of radiation brain injury of malignant glioma by ^1H-MRS

目的:利用氢质子磁共振波谱(1 H-MRS)方法,探讨容积旋转调强(VMAT)技术与三维适形放射治疗(3DCRT)技术对脑胶质瘤术后患者行放射治疗后放射性脑损伤的差别。方法:24例经临床手术证实的恶性胶质瘤(WHOⅡ～Ⅳ级胶质瘤)术后患者,其中12例进行VMAT技术放疗,另外12例进行3DCRT技术放疗,处方剂量全部为DT60-66GY/30-33F,比较2组计划的剂量分布图,并运用1 H-MRS检查2组放疗前后感兴趣区(ROI)脑组织中N-乙酰天门冬氨酸(NAA)、肌酸(Cr)、胆碱(Cho)的代谢规律,计算NAA/Cr、Cho/Cr、NAA/Cho比值,比较各组数据。结果:VMAT组剂量分布明显优于3DCRT组,放疗后2组患者NAA/Cr比值较放疗前有所降低,2组治疗后NAA/Cr比值比较差异有统计学意义(P<0.01);放疗后2组患者Cho/Cr、NAA/Cho比值较放疗前有所增高,2组治疗后NAA/Cho比值比较差异有统计学意义(P<0.01)。结论:利用VMAT技术对脑胶质瘤术后患者进行放疗,较利用3DCTR技术放疗在减轻放射性脑损伤方面有一定优势。

Objective Using proton magnetic resonance spectroscopy（^1H-MRS） method,to evaluate the difference of radiation brain injury between volumetric modulated arc therapy（VMAT） and three-dimensional conformal radiation therapy（3DCRT） in patients with postoperative glioma after radiation therapy.Methods 24 patients with malignant glioma（WHOⅡ-Ⅳ grade glioma） confirmed with clinical surgery were selected,among them 12 patients were treated with VMAT technique,and another 12 patients with 3DCRT technique,all received DT60-66GY/30-33F dose prescriptions.1H-MRS examination was performed to analyze the change of metabolites in the brain tissues of region of interest（ROI） before and after radiotherapy,and the ratios of NAA/ Cr,Cho / Cr,NAA / Cho were computed.Results The dose distribution of VMAT group was superior to 3DCRT group,the NAA/Cr in two groups after radiation were decreased compared with before radiation,there was a statistically difference in NAA/Cr after radiation between two groups（P〈0.01）.The Cho / Cr and NAA / Cho in two groups were increased compared with before radiation;after radiation,only NAA/Cho had a statistical difference between two groups（P〈0.01）.Conclusion VMAT technique is superior to 3DCTR to reduce radiation brain injury in patients with postoperative glioma.