Investigation of full-field CZT detector for emission mammotomography

The purpose of this work is to investigate and characterize a 16/spl times/20 cm/sup 2/ detector using quantized cadmium-zinc-telluride (CZT), which has been recently incorporated into the application specific emission tomograph (ASET) system for dedicated emission mammotomography. The LumaGEM 3200-S consists of 5120 total segmented pixels on 2.5 mm center-to-center pitch. The mean intrinsic energy resolution has been measured at 9.9% FWHM at 140 keV. The camera is mounted on the hemispherical gantry system for dedicated, uncompressed breast imaging, utilizing a high resolution parallel beam collimator. The modified ASET system is evaluated with planar and SPECT measurements of line sources and cold rod phantoms using simple circular tomography. Image quality is investigated through measurements of lesions in a breast background including lesion signal-to-noise ratio and contrast, using both simple vertical axis of rotation orbits and more complicated three-dimensional orbits.