Real-time dosimetry using scintillator technology in external beam radiation therapy (EBRT).

Abstract

Total Skin Electron Therapy (TSET) is a specialized radiotherapy technique used for the treatment of cutaneous T-cell lymphoma and other diffuse skin malignancies. Accurate real-time dosimetry is essential for ensuring precise dose delivery while minimizing toxicity to healthy tissues. This study presents the development and implementation of an advanced scintillator-based real-time dosimetry system designed to enhance dosimetry precision in TSET, utilizing a source-to-surface distance (SSD) of 5 meters with an intervening spoiler to optimize dose distribution. In a phantom study, nine scintillators were vertically positioned 20 cm apart on a white PVC board, alongside diodes that served as absolute dose references. Scintillator signals were captured using Cherenkov imaging cameras and fitting with correction factors were applied to ensure consistency between scintillator and diode-based dose measurements. Additionally, in vivo patient data were analyzed, revealing variations in scintillator response depending on positioning and camera selection. The results indicate that scintillators provide a feasible solution for real-time dosimetry in TSET, contingent upon strict regulation of scintillator placement and patient posture. Further optimization and standardization of scintillator positioning are necessary to enhance clinical implementation and dosimetry accuracy, ensuring reliable and precise dose monitoring in TSET applications.