Preliminary Monte Carlo study of coded aperture imaging with a CZT gamma camera system for scintimammography

Abstract

A solid-state Cadmium Zinc Telluride (CZT) gamma camera in conjunction with a Modified Uniformly Redundant Arrays (MURAs) Coded Aperture (CA) scintimammography (SM) system has been investigated using Monte Carlo simulation. The motivation is to utilise the enhanced energy resolution of CZT detectors compared to standard scintillation-based gamma cameras for scatter rejection. The effects of variations in lesion sizes and tumour-to-background-ratio were simulated in a 3D phantom geometry. Despite the enhanced energy resolution, we find that the open field geometry associated with the MURA CA imaging nonetheless requires shielding from non-specific background tracer uptake, and correction for out-of-plane activity. We find that a TBR of 20:1 is required for visualising a 10 mm wide lesion.