Experimental quantification of lesion detectability in contrast enhanced dual energy digital breast tomosynthesis

Digital breast tomosynthesis (DBT) is a three-dimensional (3D) x-ray imaging modality that has recently been employed to increase lesion conspicuity through the removal of overlying tissue. Recently, a great deal of work has been devoted to the development of contrast enhanced (CE) DBT. Radio-opaque contrast agents (e.g. iodine) are injected into patients with suspicious breast lesions, with the goal of differentiating malignant tumors from benign by imaging the contrast uptake signature associated with angiogenesis. Either temporal subtraction (TS) or dual energy (DE) subtraction may be performed to further remove structural noise from the images. The current work quantifies the change in power-law noise after either DE subtraction or TS using structured breast tissue equivalent phantoms. Additionally, iodine contrast filled phantoms were used to determine the effect of x-ray energy and image subtraction technique on the signaldifference- to-noise ratio (SDNR). Finally, we investigate the improvement in imaging performance of an amorphous selenium (a-Se) direct conversion flat panel detector with increased a-Se thickness.