A hybrid MWPC gamma ray detecting system for applications in nuclear medicine

Results are presented from prototype MWPC gas-solid hybrid imaging detectors designed for applications in nuclear medicine. Using a multi-section chamber with foil converter cathodes and a delay line readout technique, we have made a 99mTc imaging detector with a spatial resolution of 5 mm fwhm and a projected quantum efficiency of 15% for a full scale device. With lead foil cathodes the detectors design yields similar spatial resolution and quantum efficiency when positron annihilation gammas are detected. Images of positron emitters (22Na and 68Ga) are presented.