Borosilicate glass 60Co high dose rate brachytherapy thermoluminescence dosimetry

Brachytherapy is commonly used in treatment of cervical, prostate, breast and skin cancers, also for oral cancers, typically via the application of sealed radioactive sources that are inserted within or alongside the area to be treated. A particular aim of the various brachytherapy techniques is to accurately transfer to the targeted tumour the largest possible dose, at the same time minimizing dose to the surrounding normal tissue, including organs at risk. The dose fall-off with distance from the sources is steep, the dose gradient representing a prime factor in determining the dose distribution, also representing a challenge to the conduct of measurements around sources. Amorphous borosilicate glass (B2O3) in the form of microscope cover slips is recognized to offer a practicable system for such thermoluminescence dosimetry (TLD), providing for high-spatial resolution (down to < 1 mm), wide dynamic dose range, good reproducibility and reusability, minimal fading, resistance to water and low cost. Herein, investigation is made of the proposed dosimeter using a 1.25 MeV High Dose Rate (HDR) Co-60 brachytherapy source, characterizing dose response, sensitivity, linearity index and fading. Analysis of the TL glow curves were obtained using the T-max -T-stop method and first-order kinetics using GlowFit software, detailing the frequency factors and activation energy.

Automated summary

Brachytherapy is commonly used for various cancers treatment, aiming to deliver high dose to targeted tumors while minimizing damage to surrounding tissues. The use of amorphous borosilicate glass as a thermoluminescence dosimeter offers high spatial resolution, wide dynamic dose range, good reproducibility and low cost.