标题： 基于补偿器的小动物IMRT实现符合性临床前剂量绘画：应用于肿瘤缺氧 显示英文标题

标题： Compensator-based small animal IMRT enables conformal preclinical dose painting: application to tumor hypoxia

摘要： 用于临床前调强放射治疗的技术正在开发中，以通过复制临床范式来提高转化效果。 本研究首次在模型应用中比较了小动物调强放射治疗（SA-IMRT）和三维适形放射治疗（CRT）的治疗计划，该模型应用为使用实际小鼠数据的氧引导肿瘤缺氧剂量绘制。 采用了一种新的基于补偿器的平台，为十七只纤维肉瘤肿瘤的小鼠生成具有2-15个照射角度的SA-IMRT和CRT计划。 整个肿瘤接受了22.5 Gy的剂量，同时对通过电子顺磁共振成像识别的缺氧体素进行了13 Gy的同时整合增强。 使用Paddick一致性指数（CI）、均匀性和剂量体积直方图评估计划质量。 对于3个角度，SA-IMRT显著提高了剂量一致性（缺氧CI中位数=0.45对比0.17）、肿瘤剂量均匀性（11.0%对比14.3%）以及增强目标和非增强目标之间的剂量分布差异（D50%差异=13.0 Gy [理想值], 13.1 Gy [SA-IMRT], 7.3 Gy [CRT]）。 >3个照射角度与CI的显著改善无关（Wilcoxon符号等级检验，p < 0.05）。 本研究表明，SA-IMRT在放射治疗计划质量方面有显著改善，并且与当前的CRT方法相比，产生的剂量分布更接近临床环境。 显示英文摘要

摘要： Techniques for preclinical intensity modulated radiation therapy are being developed to improve translation by replicating the clinical paradigm. This study presents the first treatment planning comparison between small animal IMRT (SA-IMRT) and three-dimensional conformal radiotherapy (CRT) in a model application, oxygen-guided dose painting of tumor hypoxia, using actual mouse data. A novel compensator-based platform was employed to generate SA-IMRT and CRT plans with 2-15 beam angles for seventeen mice with fibrosarcoma tumors. The whole tumor received a dose of 22.5 Gy, with a simultaneous integrated boost of 13 Gy to hypoxic voxels identified via electron paramagnetic resonance imaging. Plan quality was assessed using the Paddick conformity index (CI), uniformity, and dose volume histograms. For 3-angles, SA-IMRT yielded significantly improved dose conformity (median hypoxic CI =0.45 versus 0.17), tumor dose uniformity (11.0% versus 14.3%), and dosimetric spread between boost and non-boost targets (D50% difference = 13.0 Gy [ideal], 13.1 Gy [SA-IMRT], 7. 3 Gy [CRT]). No significant improvement in CI was associated with >3 beam angles (Wilcoxon signed-rank test, p < 0.05). This study demonstrates that SA-IMRT provides significant improvements in radiation plan quality and yields dose distributions that more closely mimic the clinical setting relative to current CRT approaches.