PDF(Pubmed)
Abstract：
BACKGROUND: To develop a fully automated in-house gamma analysis software for the \"Cheese\" phantom-based delivery quality assurance (QA) of helical tomotherapy plans.
METHODS: The developed in-house software was designed to automate several procedures, which need to be manually performed using commercial software packages. The region of interest for the analysis was automatically selected by cropping out film edges and thresholding dose values (>10% of the maximum dose). The film-measured dose was automatically aligned to the computed dose using an image registration algorithm. An optimal film scaling factor was determined to maximize the percentage of pixels passing gamma (gamma passing rate) between the measured and computed doses (3%/3 mm criteria). This gamma analysis was repeated by introducing setup uncertainties in the anterior-posterior direction. For 73 tomotherapy plans, the gamma analysis results using the developed software were compared to those analyzed by medical physicists using a commercial software package.
RESULTS: The developed software successfully automated the gamma analysis for the tomotherapy delivery quality assurance. The gamma passing rate (GPR) calculated by the developed software was higher than that by the clinically used software by 3.0%, on average. While, for 1 of the 73 plans, the GPR by the manual gamma analysis was higher than 90% (pass/fail criteria), the gamma analysis using the developed software resulted in fail (GPR < 90%).
CONCLUSIONS: The use of automated and standardized gamma analysis software can improve both the clinical efficiency and veracity of the analysis results. Furthermore, the gamma analyses with various film scaling factors and setup uncertainties will provide clinically useful information for further investigations.
METHODS: The developed in-house software was designed to automate several procedures, which need to be manually performed using commercial software packages. The region of interest for the analysis was automatically selected by cropping out film edges and thresholding dose values (>10% of the maximum dose). The film-measured dose was automatically aligned to the computed dose using an image registration algorithm. An optimal film scaling factor was determined to maximize the percentage of pixels passing gamma (gamma passing rate) between the measured and computed doses (3%/3 mm criteria). This gamma analysis was repeated by introducing setup uncertainties in the anterior-posterior direction. For 73 tomotherapy plans, the gamma analysis results using the developed software were compared to those analyzed by medical physicists using a commercial software package.
RESULTS: The developed software successfully automated the gamma analysis for the tomotherapy delivery quality assurance. The gamma passing rate (GPR) calculated by the developed software was higher than that by the clinically used software by 3.0%, on average. While, for 1 of the 73 plans, the GPR by the manual gamma analysis was higher than 90% (pass/fail criteria), the gamma analysis using the developed software resulted in fail (GPR < 90%).
CONCLUSIONS: The use of automated and standardized gamma analysis software can improve both the clinical efficiency and veracity of the analysis results. Furthermore, the gamma analyses with various film scaling factors and setup uncertainties will provide clinically useful information for further investigations.
摘要：
背景：开发一种完全自动化的内部伽马分析软件，用于螺旋断层治疗计划的“奶酪”基于体模的交付质量保证（QA）。
方法：开发的内部软件旨在使多个程序自动化，这需要使用商业软件包手动执行。通过裁剪出胶片边缘和阈值化剂量值(>最大剂量的10%)来自动选择用于分析的感兴趣区域。使用图像配准算法将胶片测量的剂量与计算的剂量自动对准。确定最佳的胶片缩放因子,以最大化在测量剂量和计算剂量(3%/3mm标准)之间通过伽马的像素的百分比(伽马通过速率)。通过在前后方向上引入设置不确定性来重复该伽马分析。对于73个断层治疗计划，使用开发的软件的伽马分析结果与医学物理学家使用商业软件包分析的结果进行了比较。
结果：开发的软件成功地实现了伽玛分析的自动化，以保证断层治疗的质量。开发的软件计算的伽马通过率（GPR）比临床使用的软件高3.0％，平均而言。同时,对于73个计划中的1个，手动伽马分析的探地雷达高于90%(合格/不合格标准)，使用开发的软件进行的伽马分析导致失败(GPR<90%)。
结论：使用自动化和标准化的伽马分析软件可以提高临床效率和分析结果的准确性。此外，具有各种胶片比例因子和设置不确定性的伽马分析将为进一步研究提供临床有用的信息。
方法：开发的内部软件旨在使多个程序自动化，这需要使用商业软件包手动执行。通过裁剪出胶片边缘和阈值化剂量值(>最大剂量的10%)来自动选择用于分析的感兴趣区域。使用图像配准算法将胶片测量的剂量与计算的剂量自动对准。确定最佳的胶片缩放因子,以最大化在测量剂量和计算剂量(3%/3mm标准)之间通过伽马的像素的百分比(伽马通过速率)。通过在前后方向上引入设置不确定性来重复该伽马分析。对于73个断层治疗计划，使用开发的软件的伽马分析结果与医学物理学家使用商业软件包分析的结果进行了比较。
结果：开发的软件成功地实现了伽玛分析的自动化，以保证断层治疗的质量。开发的软件计算的伽马通过率（GPR）比临床使用的软件高3.0％，平均而言。同时,对于73个计划中的1个，手动伽马分析的探地雷达高于90%(合格/不合格标准)，使用开发的软件进行的伽马分析导致失败(GPR<90%)。
结论：使用自动化和标准化的伽马分析软件可以提高临床效率和分析结果的准确性。此外，具有各种胶片比例因子和设置不确定性的伽马分析将为进一步研究提供临床有用的信息。
