Detection system for the localization and measurement in vivo of small amounts of photon emitters

The purpose of this paper is to describe the design of a photon detection system for whole body in vivo detection and quantitative assessment of body burdens of 238Pu, 239Pu, or 241Am which will simultaneously yield information proportional to both the magnitude and the site(s) of deposition of photon emitters accidentally inhaled, ingested, or otherwise deposited in the body. The operating principle of the detector system, active collimation, results from the use of pulse-shape discrimination and allows spatial resolution (X, Y and Z axes) without the use of separate collimating devices and, hence, with the possibility of increased geometric detection efficiency compared to other collimated systems used to define source position