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目的:提出一种基于剂量预测的放射治疗计划质量定量评价方法,并验证该方法的临床可行性和临床价值。方法:基于45例5年以上从业经验的物理师制定的直肠癌病例,训练3D U-Net网络。利用3D U-Net网络预测得到三维剂量分布后,基于剂量预测的剂量-体积直方图(DVH)指标,建立调强放射治疗(IMRT)直肠癌计划质量评估标准,对直肠癌放疗计划进行初次打分。以预测剂量为优化目标,对放疗计划重新优化制定,并再次打分。在15例直肠癌病例上进行测试,比较优化前后计划得分情况以及剂量学参数差异,从而验证该打分方法的临床意义。结果:优化前后的计划均满足临床剂量要求。优化前的总得分为(77.21±9.74)分,优化后的总得分为(88.78±4.92)分,优化后的计划得分提升,且差异具有统计学意义(n t=-4.105, n P<0.05)。相比优化前,优化后的计划所有危及器官的n Dmax均有不同程度地降低,优化后的计划在靶区n Dmax、n V107%、HI和膀胱的n Dmax等指标上均有降低,且差异具有统计学意义(n t=2.346~5.771,n P0.05)。优化后的计划质量有一定程度提升。n 结论:本研究提出的结合剂量预测的放疗计划质量的定量评价方法,可以针对计划质量进行个性化地有效评估,有利于更好地对比审核不同物理师制定的临床计划质量,并且提供个性化的剂量指标,对临床计划的制定具有较强的指导意义。“,”Objective:To develop a dose prediction-based quantitative evaluation method of the quality of radiotherapy plans, and to verify the clinical feasibility and clinical value of the method .Methods:The 3D U-Netwas trained using the radiotherapy plans of 45 rectal cancer cases that were formulated by physicists with more than five years of radiotherapy experience. After obtaining 3D dose distribution using 3D U-Net prediction, this study established the plan quality metrics of intensity modulated radiotherapy(IMRT) rectal cancer radiotherapy plans using dose-volume histogram(DVH) indexes of dose prediction. Then, the initial scores of rectal cancer radiotherapy plans were determined.Taking the predicted dose as the optimization goal, the radiotherapy plans were optimized and scored again. The clinical significance of this scoring method was verified by comparing the scores and dosimetric parameters of the 15 rectal cancer cases before and after optimization.Results:The radiotherapy plans before and after optimization all met the clinical dose requirements. The total scores were(77.21±9.74) before optimization, and (88.78±4.92) after optimization. Therefore, the optimized radiotherapy planswon increased scores with a statistically significant difference(n t=-4.105, n P<0.05). Compared to the plans before optimization, the optimized plans show decreasedn Dmax of all organs at risk to different extents. Moreover, the n Dmax, n V107%, and HI of PTV and the n Dmax of the bladder decreased in the optimized plans, with statistically significant differences (n t=2.346-5.771, n P0.05).The quality of the optimized plans were improved to a certain extent.n Conclusions:This study proposed a dose prediction-based quantitative evaluation method of the quality of radiotherapy plans. It can be used for the effective personalized elevation of the quality of radiotherapy plans, which is beneficial to effectively compare and review the quality of clinical plans determined by different physicists and provide personalized dose indicators. Moreover, it can provide great guidance for the formulation of clinical therapy plans.