Comparison of Silicon and Scintillator Radiopharmaceutical Trackers by Monte Carlo Simulation

Radiopharmaceutical imaging at the microscale is a key capability, enabling measurement of radionuclide uptake at the cellular level, both for personalized nuclear medicine and for the development of new tracers and therapeutic agents. Conventional methods rely on the direct detection of charged particles emitted by radionuclides with autoradiographic films, or more recently using 2D active imaging techniques. We propose a novel detection concept for a 3D radiomicroscopy, tracking individual beta rays through multiple layers of position sensitive detectors. Track-based reconstruction of the source distribution in 3D enables more precise localization and dose estimates and enables more efficient imaging of thicker tissue volumes in a single sample. Two detector concepts to realize a tracking microscope are studied compared, using layers of scintillator detectors, or layers of pixelated silicon detectors. Quantification and optimization of the tracking resolution is performed, considering in particular the impact of multiple scattering. The ability to reconstruction extended sources in 3D is under investigation.