Photon Counting Detectors for X-Ray Imaging With Emphasis on CT

• Published in: IEEE transactions on radiation and plasma medical sciences Vol. 5; no. 4; pp. 422 - 440
• Main Authors: Ballabriga, R., Alozy, J., Bandi, F. N., Campbell, M., Egidos, N., Fernandez-Tenllado, J. M., Heijne, E. H. M., Kremastiotis, I., Llopart, X., Madsen, B. J., Pennicard, D., Sriskaran, V., Tlustos, L.
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 01.07.2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Application specific integrated circuits; Application specific integrated circuits (ASICs); Biomedical imaging; Computed tomography; Detectors; hybrid pixel detector; Image acquisition; Information processing; Integrated circuits; Medical imaging; Photonics; Photons; Prototypes; Sensors; Signal processing; Spatial discrimination; Spatial resolution; X ray imagery; X ray sources; X-ray imaging; X-rays
• ISSN: 2469-7311; 2469-7303
• DOI: 10.1109/TRPMS.2020.3002949

X-ray imaging is a widely used imaging modality in the medical diagnostic field due to its availability, low cost, high spatial resolution, and fast image acquisition. X-ray photons in standard X-ray sources are polychromatic. Detectors that allow to extract the "color" information of the individual X-rays can lead to contrast enhancement, improved material identification or reduction of beam hardening artifacts at the system level, if we compare them with the widely spread energy integrating detectors. Today, in the field of computed tomography (CT), prototypes of clinical grade systems based on spectral photon counting detectors are currently available for clinical research from different companies. One of the key system components in that development is the X-ray photon detector. This article reviews the photon detection hardware, from the conversion of X-rays into electrical signals to the pulse processing electronics. A review of available photon counting application specific integrated circuits (ASICs) for spectroscopic X-ray imaging is presented with emphasis on the CT medical imaging application.