A simulation and modeling study comparing the performance of a germanium orthogonal strip detector and an Anger camera

Abstract

Progress in detector technology has led to the development of a new generation of pixel-based imaging devices as potential competitors for Anger-type scintillation cameras. We modeled a 11 mm thick orthogonal strip germanium detector (GOSD) with 2 mm pitch and compared its performance to an Anger camera with a 10 mm thick NaI(Tl) crystal. The Anger camera simulation method was validated by experimental measurements made with point and volume sources. Resolution and sensitivity were determined for air and scatter measurements. The device is intended for use in breast tumor imaging, and expected device performance was simulated in response to 5 mm spherical tumors embedded in a referenced phantom geometry previously used for the simulation of a CsI pixellated detector. The thorax, the breast and the heart background contributions are considered in this phantom. A comparison of the results obtained indicates that the GOSD provides superior contrast than the Anger camera for every tumor to collimator distance. Also signal to noise ratio, FWHM and FWTM show a better response for the Germanium pixellated detector with respect to Anger camera due to better energy and spatial resolution of the germanium-based device.