Enhanced Molecular Breast Image quality through improved CZT detector performance

Molecular Breast Imaging (MBI) systems fabricated using direct-conversion detectors have demonstrated very high sensitivity and specificity in detecting breast cancer. These systems are made possible by the development of Cadmium Zinc Telluride (CZT) gamma cameras that have superior energy resolution and intrinsic spatial resolution compared to scintillation-based cameras. Image quality and patient scan time are both important metrics of these systems, which are affected by the performance of the CZT detectors and collimator. This work seeks to correlate the improvements of these metrics to improvements in CZT detector properties, as well as changes in collimator design and fabrication. To accomplish this, a phantom was designed to emulate the lesions and background seen in a typical clinical MBI scan. By collecting data sets with event statistics representative of clinical data, this phantom was then used to characterize the image quality and imaging time of CZT cameras. Cameras that were fabricated with CZT modules that were more uniform in their properties showed an improvement in image uniformity and measurable contrast of the emulated lesions in the phantoms. Thus, improvements in CZT module performance directly corresponds to a higher-quality MBI image.