Evaluation of an imaging gamma probe based on R8900U-00-C12 PSPMT

In this study we present the construction and the evaluation of a gamma probe based on a R8900U-00-C12 position sensitive photomultiplier tube coupled to a pixelated CsI(T1) crystal array with 2mm × 2mm × 3mm crystal elements and a general purpose parallel collimator. Sensitivity, energy resolution and spatial resolution were measured under 140keV irradiation, using Tc^99m. Spatial resolution was found equal to 2.4mm at zero source to collimator distance, while the sensitivity was 120cps/MBq and the energy resolution equal to 16%. Following its construction and experimental validation, the probe was simulated in GATE toolkit (version 6.0). Simulation studies were carried towards the determination of the optimal collimator that will show best compromise between high sensitivity and spatial resolution.