THE YAP CAMERA - AN ACCURATE GAMMA-CAMERA PARTICULARLY SUITABLE FOR NEW RADIOPHARMACEUTICALS RESEARCH

The YAP Camera represents a refined research instrument in nuclear med icine and pharmacology because of its overall detection efficiency com parable to an Anger Camera and its submillimeter Intrinsic spatial res olution, The YAP Camera consists of a YAP : Ce multicrystal matrix, wh ose pillars dimensions are 0.6 mm x 0.6 mm x 10 mm, optically coupled with a position sensitive PMT Hamamatsu R2486 and furnished with a par allel hole lead collimator 20 mm thick with holes diameter of 0.5 mm a nd septa of 0.15 mm, At this stage it is a miniature camera, with a fi eld of view (FOV) of 40 mm x 40 mm and a total spatial resolution of 1 .0-1.2 mm, currently used for radiotracers studies on small biological specimens, A detailed analysis of the detector position linearity and energy responses are presented in this work, The intrinsic spatial re solution is studied with three different single hole collimators (1.0, 0.3, and 0.2 mm), and a theoretical equation is presented, Three diff erent parallel hole collimators are tested to evaluate the optimal hol e and septa dimensions, Finally, it is demonstrated that two correctio n procedures are capable of recovering the image spatial homogeneity a nd of removing the statistical noise, Some phantom images show the imp ortance of the small-field YAP Camera in the radiopharmacological rese arch.