全脑照射调强放疗和常规放疗剂量学对比

Dosimetric comparision of cranial irradiation between intensity-modulated radiotherapy and conventional radiotherapy

目的:对比分析全脑照射采用调强放疗和常规放疗剂量学的差异。方法:对14例全脑照射患者分别采用调强放疗技术和常规放疗技术制作放疗计划,比较2个计划靶区适形度指数(comformity index,CI)、均匀性指数(homogeneity index,HI)和各个危及器官的受照射剂量。结果:调强放疗靶区CI优于常规放疗,靶区HI劣于常规放疗;在皮肤、脑干、视交叉、眼晶体最大剂量(D_(max))和平均剂量(D_(mean))方面,常规放疗优于调强放疗;2种放疗技术在眼球、视神经、垂体D_(max)和D_(mean)方面差异无统计学意义(P>0.01)。结论:在目前的治疗条件下,全脑照射调强放疗技术与常规放疗技术相比,没有明显优势。

Objective To compare and analyze the dosimetry difference of cranial irradiation between intensity-modulated radiotherapy and conventional radiotherapy.Method Intensity-modulated radiotherapy plans and conventional radiotherapy plans were designed for 14 cranial irradiation patients.The two kinds of plans were compared for comformity index（CI）,homogeneity index（HI）,and exposure doses to organs at risk（OAR）.Results Intensity-modulated radiotherapy had the CI better than that of conventional radiotherapy,while the HI worse than that of conventional radiotherapy.Conventional radiotherapy had the maximal exposure doses（D_（max）） and mean exposure doses（D_（mean）） to skin,brain stem,optic chiasma and eye lens better than those of intensity-modulated radiotherapy,while there were no significant differences between D_（max）and D_（mean）to eyeballs,optic nerve and pituitary gland of intensity-modulated radiotherapy and conventional radiotherapy（P〉0.01）.Conclusion Under the condition of current treatment,intensity-modulated radiotherapy has no obvious advantage over conventional radiotherapy in cranial irradiation.