Aspects of 3-D Imaging by Classical Tomography for Dual Detector PEM

Images from dual detector positron emission mammography (PEM) systems are commonly reconstructed by backprojection methods of classical tomography. Characteristics of 3–D PEM images were investigated using analytic models and computer simulations, in particular depth resolution and the quality of images in the third dimension normal to the detectors. These modeling tools provide insight into the depth blurring observed in 3-D images from experimental line source and breast phantom studies acquired with detectors built using pixellated arrays of LGSO crystals. Approaches to improved 3-D breast imaging are discussed.