Abstract：
BACKGROUND: Real-time gated proton therapy (RGPT) is a motion management technique unique to the Hitachi particle therapy system. It uses pulsed fluoroscopy to track an implanted fiducial marker. There are currently no published guidelines on how to conduct the commissioning and quality assurance. In this work we reported on our centre\'s commissioning workflow and our daily and monthly QA procedures.
METHODS: Six commissioning measurements were designed for RGPT. The measurements include imaging qualities, fluoroscopic exposures, RGPT marker tracking accuracy, temporal gating latency, fiducial marker tracking fidelity and an end-to-end proton dosimetry measurement. Daily QA consists of one measurement on marker localization accuracy. Four months daily QA trends are presented. Monthly QA consists of three measurementson the gating latency, fluoroscopy imaging quality and dosimetry verification of gating operation with RGPT.
RESULTS: The RGPT was successfully commissioned in our centre. The air kerma rates were within 15 % from specifications and the marker tracking accuracies were within 0.245 mm. The gating latencies for turning the proton beam on and off were 119.5 and 50.0 ms respectively. The 0.4x10.0 mm2 Gold AnchorTM gave the best tracking results with visibility up to 30 g/cm2. Gamma analysis showed that dose distribution of a moving and static detectors had a passing rate of more than 95 % at 3 %/3mm. The daily marker localization QA results were all less than 0.2 mm.
CONCLUSIONS: This work could serve as a good reference for other upcoming Hitachi particle therapy centres who are interested to use RGPT as their motion management solution.
METHODS: Six commissioning measurements were designed for RGPT. The measurements include imaging qualities, fluoroscopic exposures, RGPT marker tracking accuracy, temporal gating latency, fiducial marker tracking fidelity and an end-to-end proton dosimetry measurement. Daily QA consists of one measurement on marker localization accuracy. Four months daily QA trends are presented. Monthly QA consists of three measurementson the gating latency, fluoroscopy imaging quality and dosimetry verification of gating operation with RGPT.
RESULTS: The RGPT was successfully commissioned in our centre. The air kerma rates were within 15 % from specifications and the marker tracking accuracies were within 0.245 mm. The gating latencies for turning the proton beam on and off were 119.5 and 50.0 ms respectively. The 0.4x10.0 mm2 Gold AnchorTM gave the best tracking results with visibility up to 30 g/cm2. Gamma analysis showed that dose distribution of a moving and static detectors had a passing rate of more than 95 % at 3 %/3mm. The daily marker localization QA results were all less than 0.2 mm.
CONCLUSIONS: This work could serve as a good reference for other upcoming Hitachi particle therapy centres who are interested to use RGPT as their motion management solution.
摘要：
背景：实时门控质子治疗（RGPT）是日立粒子治疗系统特有的运动管理技术。它使用脉冲荧光透视来跟踪植入的基准标记。目前没有关于如何进行调试和质量保证的发布指南。在这项工作中，我们报告了我们中心的调试工作流程以及我们的每日和每月质量保证程序。
方法：为RGPT设计了六种调试测量。测量包括成像质量，透视曝光，RGPT标记跟踪精度，时间门控延迟，基准标记跟踪保真度和端到端质子剂量测定测量。每日QA包括对标记定位精度的一次测量。提出了四个月的每日QA趋势。每月QA包括基于门控延迟的三个测量，使用RGPT进行门控操作的透视成像质量和剂量学验证。
结果：RGPT在我们中心成功投入使用。空气角率与规格相差在15％以内，标记跟踪精度在0.245mm以内。打开和关闭质子束的门控延迟分别为119.5和50.0ms。0.4x10.0mm2GoldAnchorTM给出了最佳的跟踪结果，能见度高达30g/cm2。伽玛分析表明，移动和静态检测器的剂量分布在3％/3mm时的通过率超过95％。每日标记定位QA结果均小于0.2mm。
结论：这项工作可以为其他有兴趣使用RGPT作为运动管理解决方案的日立粒子治疗中心提供很好的参考。
方法：为RGPT设计了六种调试测量。测量包括成像质量，透视曝光，RGPT标记跟踪精度，时间门控延迟，基准标记跟踪保真度和端到端质子剂量测定测量。每日QA包括对标记定位精度的一次测量。提出了四个月的每日QA趋势。每月QA包括基于门控延迟的三个测量，使用RGPT进行门控操作的透视成像质量和剂量学验证。
结果：RGPT在我们中心成功投入使用。空气角率与规格相差在15％以内，标记跟踪精度在0.245mm以内。打开和关闭质子束的门控延迟分别为119.5和50.0ms。0.4x10.0mm2GoldAnchorTM给出了最佳的跟踪结果，能见度高达30g/cm2。伽玛分析表明，移动和静态检测器的剂量分布在3％/3mm时的通过率超过95％。每日标记定位QA结果均小于0.2mm。
结论：这项工作可以为其他有兴趣使用RGPT作为运动管理解决方案的日立粒子治疗中心提供很好的参考。
