Positome II: A High Efficiency Positron Imaging Device for Dynamic Brain Studies

The performance of a new positron imaging device designed for high resolution dynamic studies on the human brain is described. This unit is the first to exploit the high photoelectric efficiency of bismuth germanate (BGO) detectors which are almost 3 times as dense as NaI. In the first 4 months of clinical use some 300 patient studies have been performed. The detector performance and design criteria are discussed. The principles of operation of the coincidence circuit and computer programs are described. Finally some clinical studies are presented to demonstrate its imaging capabilities.