A preliminary clinic dosimetry study for synchrotron radiation therapy at SSRF

Abstract

Synchrotron radiation(SR)represents a unique and innovative anti-cancer treatment due to its unique physical features,including high flux density,and tunable and collimated radiation generation.The aim of this work is to assess the dosimetric properties of SR in Shanghai Synchrotron Radiation Facility(SSRF)for potential applications to clinical radiation oncology.The experiments were performed with 34 and 50 keV X-rays on the BL13W biomedical beamline of SSRF and the 6 MV X-rays from ARTISTE linac for the dosimetry study.The percentage depth dose(PDD)and the surface dose of the SR X-rays and the 6 MV photon beams were performed in solid water phantom with Gafchromic EBT3 films.All curves are normalized to the maximum calculated dose.The depth of full dose buildup is about 10μm deeper for the monoenergetic X-ray beams of 34 and 50 keV.The beam transmits through the phantom,with a linear attenuation coefficient.The profile in the horizontal plane shows that the dose distribution is uniform within the facula,while the vertical profile shows a Gaussian distribution of the dose.The penumbra is less than 0.2 mm in the horizontal profile.Gafchromic EBT film may be a useful and convenient tool for dose measurement and quality control for the high space and density resolution.It is therefore important to gain a thorough understanding about the physical features of SR before this novel technology can be applied to clinical practice.