Development and application of a small gamma camera

Abstract

This work investigates the design, construction, and application of a portable gamma camera based on a single position-sensitive photomultiplier tube (PSPMT) rather than an array of conventional phototubes. The PSPMT is an innovation in photomultiplier design that allows two-dimensional position information to be obtained from a single phototube. PSPMT-based portable gamma cameras can have several distinct advantages over portable systems using conventional technology: lower weight, reduced electronics, and smaller size. This design can be incorporated as modules in conjugate imaging, orthogonal view, or ring detector systems, or even in large-area planar imagers. The PSPMT design is applicable for diagnostic clinical procedures and for basic biomedical research. Two small gamma camera (SGC) systems have been constructed. Computer simulations and physical measurements have been applied to the performance characterization of the SGC. The SGC incorporates a maximum-likelihood position estimation scheme. The intrinsic resolution of the SGC is 1.7 mm FWHM (3.2 mm FWTM) at the center of the 48 mm×48 mm field of view. The SGC has been evaluated for several nuclear medicine imaging applications as well as laboratory research imaging. The clinical applications include planar and tomographic imaging. Radiotracer imaging with the SGC has been applied to the in vivo investigation of electroporation injury and tissue repair. © 1997, American Association of Physicists in Medicine. All rights reserved.