AUTHOR=Kutsaev Sergey V. , Agustsson Ronald , Boucher Salime , Carriere Paul , Ghoniem Nasr , Kaneta Kenichi , Kravchenko Maksim , Li Alan , Moro Adam , Patel Sohun , Sheng Ke
TITLE=Feasibility study of high-power electron linac for clinical X-ray ROAD-FLASH therapy system
JOURNAL=Frontiers in Medical Engineering
VOLUME=2
YEAR=2024
URL=https://www.frontiersin.org/journals/medical-engineering/articles/10.3389/fmede.2024.1382025
DOI=10.3389/fmede.2024.1382025
ISSN=2813-687X
ABSTRACT=Introduction: This study examines how a practical source of X-ray radiation, capable of delivering unprecedented X-ray of 100 Gy/s at 1 m for X-ray FLASH radiotherapy can be designed.
Methods: We proposed the design of a linac, capable of accelerating 18 MeV 8 mA electron beam with further conversion to bremsstrahlung X-rays. The design is based on L-band traveling wave accelerating structures with high power efficiency, operating in a short-burst/long-pulse regime that allows operating power supply in a regime, beyond its specifications.
Results: This study demonstrates the feasibility of a high-power linac for a clinical X-ray FLASH therapy system, using detailed analysis and simulations. Despite ∼500x higher output than a standard clinical linac, the design utilizes available accelerator components for maximal practicality.
Discussion: Recent studies have demonstrated that the FLASH effect that allows to effectively kill tumor cells while sparing normal tissue occurs when large dose rates (≥40 Gy/s) are delivered in less than 1 s. Photons are very attractive since modest energies of several MeV are needed, which can be achieved with compact and cost-efficient accelerators. However, since the efficiency of electron-to-photon conversion is only a few percent, the required beam intensity must be an order of magnitude higher than that state-of-the-art accelerators can provide. The proposed ROAD-FLASH accelerator layout allows achieving both the FLASH dose rate and superior dose conformity, comparing to the similar projects. The current paper focuses on providing a technical roadmap for building an economical and practical linear accelerator for ROAD X-ray FLASH delivery.