脑胶质瘤三维适形放射治疗与调强放射治疗的剂量学比较

Dosimetric comparison of three-dimensional conformal and intensity modulated radiotherapy in brain glioma

目的评价脑胶质瘤调强放射治疗较三维适形放射治疗的剂量学优势。方法本研究采用10例脑胶质瘤患者，针对所有患者分别进行3DCRT和IMRT的计划设计，利用剂量体积直方图评价不同照射技术中靶区和正常组织照射剂量、适形度指数和不均匀性指数。处方剂量为60Gy。结果IMRT计划脑干最大剂量和受照体积、患侧腮腺平均剂量和脊髓最大剂量均低于3DCRT计划。对于靶区适形度指数，IMRT计划优于3DCRT计划；对于不均匀性指数，两种计划模式的差异没有统计学意义。结论在脑胶质瘤放疗中应用IMRT可以明显降低脑干的剂量和受照体积，为靶区剂量的提高提供了可能性。

Objective To investigate the dosimetry advantages of intensity modulated radiotherapy （IMRT）of brain glioma compared with that of three-dimensional conformal radiotherapy （3D CRT）. Methods Ten patients with brain glioma were enrolled in this study. Three-dimensional conformal and intensity modulated radiotherapy plans were performed for each patient. The dose distributions of target volume and normal tissues, conformal index （CI） and heterogeneous index （HI） were analyzed using the dose-volume histogram （DVH）. The prescription dose was 60 Gy in 30 fractions. Results IMRT plans decrease the maximum dose and volume of brainstem, mean dose of affected side parotid and maximum dose of spinal-cord. The C1 for PTV of IMRT was superior to that of 3D CRT, the HI for PTV has no statistical significance of the two model plans. Conclusions IMRT plans can obviously decrease the dose and volume of brainstem. IMRT is a potential method in the treatment of brain glioma, and dose escalation was possible in patients with brain glioma.