【摘要】 目的:利用挡铅野中野技术与射野权重优化,调节各方向剂量强度,探讨野中野适形与IMRT的相似性。方法:以1例鼻咽癌为研究对象,对该病例做适形计划和常规二维计划,并与IMRT相比较,评价计划靶区及危及器官的受照剂量、DVH及各特征指标值。结果:野中野与常规二维计划靶区平均剂量分别为75.9Gy、73.0Gy;腮腺受量V35分别为49%、88%,对比调强靶区平均剂量74Gy、腮腺V35约为50%。结论:在没有多叶光栅MLC时,野中野适形计划及对危及器官的保护方面明显优于常规二维计划,在靶区均匀性与调强计划有较小差异,能实现近似IMRT的结果,解决常规二维难以胜任的凹形靶区和危及器官的高损伤情况,具有较好的临床价值。更多还原

【Abstract】 Objective: Using lead block field-in-field and beam weight optimization by adjusting dose intensity of different directions,to explore the similarity between field-in-field 3DCRT and IMRT.Methods: Using one patient with nasopharyngeal cancer as research subject,two different plans were made by used of field-in-field conformal radiotherapy method and normal two-dimensional radiotherapy method respectively.In contrast to IMRT,the two plans were evaluated with radiation doses on the plan target and organs at risk,DVH and other critical attributes.Results: The mean target doses of field-in-field 3DCRT and normal two-dimensional radiotherapy were 75.9Gy and 73.0Gy respectively,the V35 of parotid were 49% and 88% repectively.In IMRT plan the mean target dose was 74Gy,V35 of parotid wasabout 50%.Conclusion: When used without multi-leaf collimator,field-in-field 3DCRT holds significant advantage in protecting organs at risk comparing with normal two-dimensional radiotherapy,and acts slight different on dose uniformity of target comparing with IMRT.Field-in-field conformal radiotherapy can achieve similar result with IMRT.Conformal radiotherapy acts well with concave targets and provides good protection to organs at risk which normal two-dimensional radiotherapy can’t achieve.It has very good clinic significance.更多还原