Characterisation of a Fricke gel compound adopted to produce dosimetric catheters for in vivo dose measurements in HDR brachytherapy

Radiation doses delivered to the patient during high dose rate brachytherapy treatments are susceptible to many inaccuracies and may not accurately match the planned doses. Novel Fricke gel dosimetric catheters (FGDC) were developed in the laboratory to be used for in vivo measurements of high dose rate brachytherapy treatments and represent possible tools to increase treatment accuracy. In this study, the dosimetric compound adopted to achieve FGDC was studied in terms of dose sensitivity and linearity, and some potentialities and limits of its application were investigated. Results show that at doses higher than 400 cGy, the dosimeter response is linear with the delivered dose until a saturation effect is observed at doses higher than 2800 cGy. However, saturation is reached at lower doses as well with dose rates higher than 400 cGy/min.