PET DETECTOR MODULES BASED ON NOVEL DETECTOR TECHNOLOGIES

A successful PET detector module must identify 511 keV photons with: h igh efficiency (> 85%), high spatial resolution (<5 mm fwhm), low cost (<$600/in.(2)), low dead time (<4 mu s in.(2)), good timing resolutio n (<5 ns fwhm for conventional PET, < 200 ps fwhm for time of flight), and good energy resolution (< 100 keV fwhm), where these requirements are listed in order of decreasing importance. The ''high efficiency'' requirement also implies that the detector modules must pack together without inactive gaps. Several novel and emerging radiation detector technologies could improve the performance of PET detectors. Avalanche photodiodes, PIN photodiodes, metal channel dynode photomultiplier tu bes, and new scintillators all have the potential to improve PET detec tors significantly.