Material Decomposition Using Multi-Energy Imaging with Photon Counting Detectors

The current screening tool for breast cancer is digital mammography (DM). DM is based on the principle that x-ray photons are absorbed by materials differently. Breast cancer screening relies on the detection of tumors and micro calcifications. One of the primary challenges in breast imaging is to differentiate healthy, glandular and adipose, versus unhealthy tissues in the breast. Certain plastics can be used as a substitute to mimic the x-ray absorption of breast tissue. Micro calcifications can be replaced with hydroxyapatite (HA). To improve diagnosis, contrast agents, like iodine, could be used in DM. Iodine is injected intravenously and the tumor will temporarily absorb it. Dual energy subtraction techniques are used for enhanced iodine contrast imaging. In order to separate iodine from calcification, multi-energy imaging is desired. Multi-energy imaging is the acquisition of three or more different images at different energies. This data can be used for material decomposition where the distribution of each of the materials is found simultaneously.