Challenges in Optimization of a Stationary Tomographic Molecular Breast Imaging System

Abstract

A prototype Molecular Breast Imaging (MBI) system is currently under development, motivated by the need of a practical low-dose system for use in patients with dense breast tissue, where conventional mammography is limited. The system is based on dual opposing CZT detector arrays and multi-pinhole collimators which allow for multiplexing in the projection data. We have performed optimization of various design parameters based on either contrast-to-noise ratio (CNR) in the reconstructed images or area under the localization receiver operating characteristics curve (LROC-AUC) obtained using the scan statistic model. The optimizations were based on simulated data, and the parameters investigated were pinhole size and opening angle, pinhole separation and collimator-to-detector separation. The two optimization approaches resulted in similar design parameters, allowing for reconstruction of tomographic images with high CNR and lesion detectability, which can lead to a reduced dose or scan time as compared to planar MBI.