Microwave imaging of breast tumors with contrast agents: Theoretical study of dielectric contrast enhancement requirements

We propose a microwave breast tumor imaging technique that exploits changes in tumor dielectric properties resulting from the use of a contrast agent. A linear system, whose solution is the agent-induced change in dielectric properties, is established based on a microwave inverse scattering formulation. The linear system is solved using a sparsity regularizer. We identify the minimum required increase in tumor dielectric properties introduced by a contrast agent such that a 1-cm-diameter tumor can be accurately localized in 3D realistic numerical breast phantoms across all breast density classes. The results may be used to guide future contrast agent development.