Feasibility study of beta particle imaging from Lu-177 with a YAP(Ce) radiation detector

Abstract Lutetium-177 (Lu-177) is a promising radionuclide for use in targeted radionuclide therapy. While in vivo imaging has traditionally been performed by detecting gamma photons emitted from Lu-177 using gamma cameras, imaging based on beta particles has been reported far less frequently. To address this, we developed a YAP(Ce)-based radiation imaging detector capable of visualizing beta particles, X-rays, and gamma photons emitted from Lu-177, and we evaluated its imaging performance. The detector consists of a 0.5 mm-thick YAP(Ce) scintillator plate optically coupled to a 1-inch square position-sensitive photomultiplier tube (PSPMT). Interaction positions of detected radiation were determined using Anger logic. The spatial resolution of the detector for beta particles — taking into account the contribution of accompanying gamma photons and X-rays — was approximately 0.7 mm full width at half maximum (FWHM). Under these conditions, the relative sensitivity for beta particles, including the associated gamma photons and X-rays, was more than 5 times higher than that for gamma photons and X-rays alone. These findings indicate that beta particle imaging provides both high spatial resolution and high sensitivity, suggesting it as a promising technique for the detection and imaging of Lu-177 emissions.