Evaluation of the InterDosi code in estimating S-values with the digimouse voxelized mouse phantom

Abstract

This study delves into the realm of internal dosimetry in small animals, focusing on the crucial role of S-values (absorbed dose rate per unit activity). The primary objective is to enhance our understanding of ionizing radiation distribution and optimize treatment strategies involving multidisciplinary approach which integrates dosimetry data, computational modeling, clinical expertise, and patient-specific factors to deliver safe, effective, and personalized cancer treatments, paving the way for more effective and tailored radiotherapeutic interventions and diagnostic cancer research. The research specifically targets the assessment of radiation doses absorbed in target organs and adjacent tissues during targeted radionuclide therapy with iodine-131 and yttrium-90. Executed on the ERSN (Radiations and Nuclear Systems Laboratory) computing grid, the study employed optimized calculations using 20 CPU (Central Processing Unit) cores for each of the 103 SAF (Specific Absorbed Fractions) grid sizes of photons and electrons. The InterDosi code, a user-friendly tool, streamlined S-value estimation within the Digimouse phantom. Nine source organs and the entire murine anatomy were comprehensively evaluated. The G4EMLiverMorePhysics package ensured high-confidence dosimetric coefficient simulations. S-values revealed insights into absorbed dose influences, including organ mass and inter-organ distance. Comparative analyses were conducted with reference data, which involved a simplified S-value calculation. The results aligned well with the reference data, especially with similar SAF grid sizes for electrons and photons. Accuracy improved with larger grid sizes. This study confirms InterDosi's effectiveness, highlighting its adaptability and precision in estimating S-values for various radionuclides, making it a valuable tool for evaluating radiation doses in murine anatomy.