Dosimetric evaluation of GAFCHROMIC® XR type T and XR type R films

Abstract

The high spatial resolution of radiochromic film makes it ideal for dosimetric measurements and dose distributions in regions of high dose gradient. IMRT, intravascular brachytherapy, and eye-plaque radiation therapy demand precise spatial dosimetric calculations, which are not possible with conventional dosimeters, such as TLDs and ionization chambers. Recently, new highly sensitive GAFCHROMIC® XR type T and type R films have been developed for radiation dosimetry in the low photon energy range. Dosimetric characteristics (i.e. linearity, post exposure density growth, energy dependence, dose rate dependence and UV light sensitivity) of these new films have been investigated. To evaluate the clinical applications of these films, their characteristics have been compared with other commercially available film models. GAFCHROMIC® XR type T and type R films were found to be more sensitive to low energy doses as compared to GAFCHROMIC® MD 55 films.