Imaging performance of a multiwire proportional-chamber positron camera

A fully three dimensional positron camera is presented, made of six multiwire proportional chamber modules arranged to form the lateral surface of a hexagonal prism. A true coincidence rate of 56000 c/s is expected with an equal accidental rate for a 400 micron Ci activity uniformly distributed in an approximately 3.1 water phantom. A detailed Monte Carlo program was used to investigate the dependence of the spatial resolution on the geometrical and physical parameters. A spatial resolution of 4.8 mm FWHM was obtained for a F-18 point like source in a 10 cm radius water phantom. The main properties of the limited angle reconstruction algorithms are described in relation to the proposed detector geometry.