Abstract:

Abstract: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.

Key words: volumetric modulated arc therapy, three-dimensional conformal radiation therapy;magnetic resonance spectroscopy, malignant glioma