PDF(Pubmed)
Abstract：
OBJECTIVE: To design a patient specific quality assurance (PSQA) process for the CyberKnife Synchrony system and quantify its dosimetric accuracy using a motion platform driven by patient tumor traces with rotation.
METHODS: The CyberKnife Synchrony system was evaluated using a motion platform (MODUSQA) and a SRS MapCHECK phantom. The platform was programed to move in the superior-inferior (SI) direction based on tumor traces. The detector array housed by the StereoPhan was placed on the platform. Extra rotational angles in pitch (head down, 4.0° ± 0.15° or 1.2° ± 0.1°) were added to the moving phantom to examine robot capability of angle correction during delivery. A total of 15 Synchrony patients were performed SBRT PSQA on the moving phantom. All the results were benchmarked by the PSQA results based on static phantom.
RESULTS: For smaller pitch angles, the mean gamma passing rates were 99.75% ± 0.87%, 98.63% ± 2.05%, and 93.11% ± 5.52%, for 3%/1 mm, 2%/1 mm, and 1%/1 mm, respectively. Large discrepancy in the passing rates was observed for different pitch angles due to limited angle correction by the robot. For larger pitch angles, the corresponding mean passing rates were dropped to 93.00% ± 10.91%, 88.05% ± 14.93%, and 80.38% ± 17.40%. When comparing with the static phantom, no significant statistic difference was observed for smaller pitch angles (p = 0.1 for 3%/1 mm), whereas a larger statistic difference was observed for larger pitch angles (p < 0.02 for all criteria). All the gamma passing rates were improved, if applying shift and rotation correction.
CONCLUSIONS: The significance of this work is that it is the first study to benchmark PSQA for the CyberKnife Synchrony system using realistically moving phantoms with rotation. With reasonable delivery time, we found it may be feasible to perform PSQA for Synchrony patients with a realistic breathing pattern.
METHODS: The CyberKnife Synchrony system was evaluated using a motion platform (MODUSQA) and a SRS MapCHECK phantom. The platform was programed to move in the superior-inferior (SI) direction based on tumor traces. The detector array housed by the StereoPhan was placed on the platform. Extra rotational angles in pitch (head down, 4.0° ± 0.15° or 1.2° ± 0.1°) were added to the moving phantom to examine robot capability of angle correction during delivery. A total of 15 Synchrony patients were performed SBRT PSQA on the moving phantom. All the results were benchmarked by the PSQA results based on static phantom.
RESULTS: For smaller pitch angles, the mean gamma passing rates were 99.75% ± 0.87%, 98.63% ± 2.05%, and 93.11% ± 5.52%, for 3%/1 mm, 2%/1 mm, and 1%/1 mm, respectively. Large discrepancy in the passing rates was observed for different pitch angles due to limited angle correction by the robot. For larger pitch angles, the corresponding mean passing rates were dropped to 93.00% ± 10.91%, 88.05% ± 14.93%, and 80.38% ± 17.40%. When comparing with the static phantom, no significant statistic difference was observed for smaller pitch angles (p = 0.1 for 3%/1 mm), whereas a larger statistic difference was observed for larger pitch angles (p < 0.02 for all criteria). All the gamma passing rates were improved, if applying shift and rotation correction.
CONCLUSIONS: The significance of this work is that it is the first study to benchmark PSQA for the CyberKnife Synchrony system using realistically moving phantoms with rotation. With reasonable delivery time, we found it may be feasible to perform PSQA for Synchrony patients with a realistic breathing pattern.
摘要：
目的：为CyberknifeSynchrony系统设计患者特定的质量保证（PSQA）过程，并使用由旋转的患者肿瘤痕迹驱动的运动平台量化其剂量测定准确性。
方法：使用运动平台（MODUSQA）和SRSMapCHECK体模评估了CyberkifeSynchrony系统。平台被编程为基于肿瘤迹线在上-下(SI)方向上移动。由StereoPhan容纳的检测器阵列被放置在平台上。额外的俯仰旋转角度(头部向下,将4.0°±0.15°或1.2°±0.1°）添加到移动的体模中，以检查机器人在交付过程中的角度校正能力。共有15例Synchrony患者在移动体模上进行了SBRTPSQA。所有结果均以基于静态体模的PSQA结果为基准。
结果：对于较小的俯仰角，平均伽玛通过率为99.75%±0.87%，98.63%±2.05%,93.11%±5.52%，对于3%/1毫米，2%/1毫米，和1%/1毫米，分别。由于机器人的角度校正有限，因此对于不同的俯仰角，观察到通过率存在很大差异。对于较大的俯仰角，相应的平均通过率下降到93.00%±10.91%，88.05%±14.93%,和80.38%±17.40%。当与静态幻像比较时，对于较小的俯仰角，没有观察到显著的统计差异(3%/1mm时p=0.1)，而对于较大的俯仰角，观察到较大的统计差异（所有标准p<0.02）。所有的伽马通过率都提高了，如果应用移位和旋转校正。
结论：这项工作的意义在于，它是第一个对CyberkifeSynchrony系统进行PSQA基准测试的研究，该系统使用具有旋转的现实移动体模。合理的交货时间，我们发现对具有真实呼吸模式的同步患者进行PSQA可能是可行的.
方法：使用运动平台（MODUSQA）和SRSMapCHECK体模评估了CyberkifeSynchrony系统。平台被编程为基于肿瘤迹线在上-下(SI)方向上移动。由StereoPhan容纳的检测器阵列被放置在平台上。额外的俯仰旋转角度(头部向下,将4.0°±0.15°或1.2°±0.1°）添加到移动的体模中，以检查机器人在交付过程中的角度校正能力。共有15例Synchrony患者在移动体模上进行了SBRTPSQA。所有结果均以基于静态体模的PSQA结果为基准。
结果：对于较小的俯仰角，平均伽玛通过率为99.75%±0.87%，98.63%±2.05%,93.11%±5.52%，对于3%/1毫米，2%/1毫米，和1%/1毫米，分别。由于机器人的角度校正有限，因此对于不同的俯仰角，观察到通过率存在很大差异。对于较大的俯仰角，相应的平均通过率下降到93.00%±10.91%，88.05%±14.93%,和80.38%±17.40%。当与静态幻像比较时，对于较小的俯仰角，没有观察到显著的统计差异(3%/1mm时p=0.1)，而对于较大的俯仰角，观察到较大的统计差异（所有标准p<0.02）。所有的伽马通过率都提高了，如果应用移位和旋转校正。
结论：这项工作的意义在于，它是第一个对CyberkifeSynchrony系统进行PSQA基准测试的研究，该系统使用具有旋转的现实移动体模。合理的交货时间，我们发现对具有真实呼吸模式的同步患者进行PSQA可能是可行的.
