The Department of Radiation Oncology, The Ohio State University Wexner Medical Center, United States of America.
Phys Med Biol. 2023 Sep 22;68(19). doi: 10.1088/1361-6560/acf63e.
. Commercial electron FLASH platforms deliver ultra-high dose rate doses at discrete combinations of pulse parameters including pulse width (PW), pulse repetition frequency (PRF) and number of pulses (), which dictate unique combinations of dose and dose rates. Additionally, collimation, source to surface distance, and airgaps also vary the dose per pulse (DPP). Currently, obtaining pulse parameters for the desired dose and dose rate is a cumbersome manual process involving creating, updating, and looking up values in large spreadsheets for every treatment configuration. This work presents a pulse parameter optimizer application to match intended dose and dose rate precisely and efficiently.. Dose and dose rate calculation methods have been described for a commercial electron FLASH platform. A constrained optimization for the dose and dose rate cost function was modelled as a mixed integer problem in MATLAB (The MathWorks Inc., Version9.13.0 R2022b, Natick, Massachusetts). The beam and machine data required for the application were acquired using GafChromic film and alternating current current transformers (ACCTs). Variables for optimization included DPP for every collimator, PW and PRF measured using ACCT and airgap factors.. Using PW, PRF,and airgap factors as parameters, a software was created to optimize dose and dose rate, reaching the closest match if exact dose and dose rates are not achievable. Optimization took 20 s or less to converge to results. This software was validated for accuracy of dose calculation and precision in matching prescribed dose and dose rate.. A pulse parameter optimization application was built for a commercial electron FLASH platform to increase efficiency in dose, dose rate, and pulse parameter prescription process. Automating this process reduces safety concerns associated with manual look up and calculation of these parameters, especially when many subjects at different doses and dose rates are to be safely managed.
. 商业电子 FLASH 平台以离散的脉冲参数组合提供超高剂量率剂量，这些参数包括脉冲宽度 (PW)、脉冲重复频率 (PRF) 和脉冲数 ()，它们决定了剂量和剂量率的独特组合。此外，准直、源皮距和气隙也会改变每个脉冲的剂量 (DPP)。目前，获得所需剂量和剂量率的脉冲参数是一个繁琐的手动过程，涉及为每个治疗配置创建、更新和查找大型电子表格中的值。本工作介绍了一种脉冲参数优化器应用程序，可精确、高效地匹配预期剂量和剂量率。. 已为商业电子 FLASH 平台描述了剂量和剂量率计算方法。在 MATLAB 中，将剂量和剂量率成本函数的约束优化建模为一个混合整数问题 (The MathWorks Inc.，Version9.13.0 R2022b，Natick，Massachusetts)。应用所需的束流和机器数据是使用 GafChromic 胶片和交流电流互感器 (ACCT) 获得的。优化的变量包括每个准直器的 DPP、使用 ACCT 测量的 PW 和 PRF 以及气隙因子。. 使用 PW、PRF 和气隙因子作为参数，创建了一个软件来优化剂量和剂量率，如果无法实现精确的剂量和剂量率，则可以达到最接近的匹配。优化在 20 秒或更短的时间内收敛到结果。该软件已验证剂量计算的准确性和匹配规定剂量和剂量率的精度。. 为商业电子 FLASH 平台构建了脉冲参数优化应用程序，以提高剂量、剂量率和脉冲参数处方过程的效率。自动化此过程可降低与手动查找和计算这些参数相关的安全问题，特别是在需要安全管理不同剂量和剂量率的许多受试者时。
