Radiochromic film dosimetry in radiotherapy: a survey of current practice in the United Kingdom

Objectives To establish the variation in film dosimetry usage in radiotherapy centres across the United Kingdom. To identify consensus and highlight areas of potential improvement to enhance radiotherapy dosimetry verification with film. Methods A survey questionnaire was designed by members of the Institute of Physics and Engineering in Medicine Interdepartmental Dosimetry Audit Group via Microsoft Forms and distributed to all Heads of Radiotherapy Physics in the United Kingdom. The survey was open from June 19, 2023, to July 31, 2023. Results Forty responses were received from the 62 radiotherapy centres in the United Kingdom, of which 58% were currently using film dosimetry and a further 7 were keen to commence use. Many reported film use had decreased in recent years but was still valuable particularly for commissioning and implementing new techniques. The variation and consensus of methods for film dosimetry calibration, measurement, and application was established. A review of barriers to implementation and methods to reduce uncertainty were included in the assessment. Conclusions A comprehensive assessment of film dosimetry usage in radiotherapy in the United Kingdom has been collated, which demonstrates a wide variation in methods, across typical clinical users, but maintains film as a valuable dosimetry option. Advances in knowledge This research provides a snapshot of current film dosimetry use across the United Kingdom. It examines the variation and consensus of practice to which individual users can compare their systems, and identifies opportunities to improvement in the accuracy of film dosimetry.