Dosimetry evaluation of ¹⁹²Ir Flexisource using gafchromic EBT3 film

Abstract

Abstract Introduction: Brachytherapy is a widely used cancer treatment technique requiring precise dose delivery for optimal outcomes. This study evaluates the dosimetric properties of the ${{\rm{\;}}^{192}}$ Ir Flexisource using Gafchromic EBT3 film, adhering to American Association of Physicists in Medicine guidelines. Methods: The EBT3 film was calibrated with a linear accelerator to establish the relationship between optical density and absorbed dose. Measurements were conducted in a water-equivalent solid phantom to simulate human tissue. The dosimetric properties measured included the dose rate constant, radial dose function and anisotropy function. Results: The results showed a close alignment with reference data: a maximum deviation of 3·1% for the dose rate constant, 2·3% for the radial dose function and 5·67% for the anisotropy function. These deviations are within acceptable limits, indicating high accuracy. Conclusions: Gafchromic EBT3 film demonstrates reliable dosimetric measurement in high-dose rate brachytherapy. The film’s accuracy in evaluating the ${{\rm{\;}}^{192}}$ Ir Flexisource ensures precise treatment delivery and enhances patient safety, supporting its continued use in clinical practice.