Although many technologies, such as an electronic portal imaging device, a software-based quality assurance system, an ion chamber array, etc. , have been developed for the purpose of quality assurance of radiotherapy planning, radiochromic film is still one of the most reliable technologies and is being widely used. In particular, compared with other technologies, EBT3 film has unique advantages, including its unlimited spatial resolution, relatively small volume and waterproof quality, which means it can be used inside the patient’s body. The main obstacle to using EBT3 film is that various equations have to be used in the calibration process, which makes it very sensitive to the results. The manufacturer provides a fitting function, but many software programs and researchers use their own functions. In this study, some functions normally used for calibrating EBT3 films are compared by analyzing a couple of characteristics in the course of fitting the function to the measured values. Although our study shows the lack of a suitable fitting function that works well in every situation, it can provide valuable insight into selecting suitable functions for fitting in a clinical setting.

中文翻译：

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为放射治疗中的胶片剂量测定选择拟合函数的注意事项

尽管已经开发了许多技术，例如电子门户成像设备、基于软件的质量保证系统、离子室阵列等，用于放射治疗计划的质量保证，但放射变色膜仍然是最可靠的之一。技术并得到广泛应用。特别是与其他技术相比，EBT3薄膜具有独特的优势，包括无限的空间分辨率、相对较小的体积和防水质量，这意味着它可以在患者体内使用。使用 EBT3 胶片的主要障碍是在校准过程中必须使用各种方程，这使得它对结果非常敏感。制造商提供了拟合功能，但许多软件程序和研究人员使用自己的功能。在这项研究中，在将函数拟合到测量值的过程中，通过分析几个特性来比较通常用于校准 EBT3 薄膜的一些函数。尽管我们的研究表明缺乏适用于各种情况的合适拟合函数，但它可以为选择合适的函数以在临床环境中拟合提供有价值的见解。