CHARACTERIZATION AND EXPERIMENTAL MEASUREMENTS OF SCATTER DOSE AT CARDIOLOGIST'S EYES DURING PAEDIATRIC INTERVENTIONAL CARDIOLOGY PROCEDURES IN COSTA RICA.

ABSTRACT

This paper presents the results of the first characterization and experimental measurements of scatter dose at cardiologist's eyes for the only X-ray system that performs all paediatric Interventional cardiology procedures in Costa Rica. Entrance surface air kerma (ESAK) and the scatter dose values were measured on phantoms of 4-20 cm thicknesses of polymethyl methacrylate slabs. Image quality was evaluated using DICOM images of a test object Leeds TOR 18-FG, through the numerical parameters signal-to-noise ratio (SNR), high-contrast spatial resolution (HCSR) and figure of merit (FOM). When PMMA thickness is increased and during a move from low fluoroscopy to cine modes, ESAK, SNR, HCSR and FOM values range from 0.44 to 391.0 µGy fr-1; 2.8 to 14.89; 3.17 to 15.54 and 0.51 to 79.94, respectively. The highest scattered dose rates recorded during the simulations were 1.79 and 8.04 mSv h-1 for the high fluoroscopy and cine modes, respectively.