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

The high spatial resolution of radiochromic film makes it ideal for dosimetric measurements and dose distributions in regions of high dose gradient. Intensity-modulated radiation therapy, intravascular brachytherapy, and eye-plaque radiation therapy demand precise spatial dosimetric calculations. Such precision is not possible with conventional dosimeters, such as thermoluminescent dosimeters and ionization chambers. Recently, new GAFCHROMIC XR type T and type R films have been developed for radiation dosimetry, specifically in interventional radiology procedures. Dosimetric characteristics (i.e., linearity, post-exposure density growth, energy dependence, dose-rate dependence, and UV light sensitivity) of these new films were investigated. To evaluate the clinical applications of these films, their characteristics were 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 with GAFCHROMIC MD-55 films.