Gamma Camera with Self-collimation and Compton Imaging

Self-collimation is a novel approach in gamma imaging that employs the detector itself to play the role of collimation, enabling high resolution and sensitivity. However, for high-energy gamma rays (e.g., 511 keV), inter-scintillator scattering becomes more pronounced and reduces imaging performance. Compton imaging is a well-established approach that has advantages in imaging high-energy gamma rays, albeit with limited spatial resolution. In this work, we present a proof-of-concept study for a gamma camera that combines the principles of self-collimation and Compton imaging. The camera consists of 1) interspaced mosaic scintillator bars with dual-end SiPM readouts for self-collimation imaging, and 2) a mechanism to incorporate Compton coincidence events for image formation. Monte Carlo simulations demonstrate that incorporating Compton imaging leads to improved performance in terms of reducing noise-induced artifacts and enhancing spatial resolution. We believe that integrating self-collimation and Compton imaging can facilitate the application of high-energy gamma ray imaging in SPECT and expand the range of available radiopharmaceuticals.