Experimental characterization and Monte Carlo simulations of the dose enhancement on the millimeter scale of PAGAT infused with Gadolinium

SANTIBÁÑEZ, MAURICIO; FUENTEALBA, M.; VEDELAGO, JOSÉ; CHACÓN, DAVID; MATTEA, F.; VALENTE, M.

RADIATION PHYSICS AND CHEMISTRY (OXFORD)

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2021

0969-806X

his study reports on the determination of the K-edge dose enhancement factor achieved in a polymer gel dosimeter based on acrylamide, known as PAGAT, infused with a high concentration of a clinical gadolinium-based compound. PAGAT dosimeters infused with gadolinium concentrations of 10 mg/mL and 20 mg/mL are characterized in terms of dose-response and sensitivity, obtaining the dose enhancement between two beam qualities for these Gd concentrations of clinical interest. Additionally, the dose enhancement ratio between these two concentrations was evaluated for each beam quality. To this aim, Gadodiamide solution, a Gd-based agent commonly used in clinics for magnetic resonance scanning, is used to manufacture Gd-infused dosimeters that are further irradiated with a 50 kVp X-ray beam in order to assess dose enhancement contributions exclusively from absorption from lower edges (L, M, etc.); subsequently, a 160 kVp spectrum optimized by yttrium and indium filtration is used to evaluate