Synthetic film-based testing of film quality assurance software accuracy.

Film quality assurance software is an integral component of patient-specific quality assurance for various radiation techniques where high degrees of geometrical and dosimetric accuracy are required. Evaluating the accuracy of film quality assurance software products has relied on various techniques ranging from comparative analyses, measurements with phantoms and other detectors, along with confidence from industry-standard peer reviews. The aim of this work was to determine if a series of synthetically created film and DICOM images can be used to test the accuracy of certain patient specific quality assurance metrics used in film quality assurance software packages. The synthetic images have been engineered to simulate radiographic film scanned TIFF images and treatment planning system exported DICOM files. Each pair of images were designed to test a particular component of the software's ability to process curve fitting, dosimetric differences, distance to agreement, percentage threshold and gamma analysis. It was found that synthetic film could simulate radiographic scanned films and treatment planning system DICOM planes and provide the physicist with empirical data on the accuracy of the mentioned metrics. The series of tests also assisted the physicist in identifying optimal calibration models, validating geometric and dosimetric variations, and offering insights into potential differences in lower dose penumbras.