Photon counting detectors with energy binning can improve CT performance by counting and binning each x-ray detected. Photon counting x-ray detectors applied to mammography and radiography have shown a dose reduction of 40% to 400% while maintaining sufficient contrast for these applications. For use in CT these detectors are limited, due to an upper bound in terms of their maximum count rate, and advances in maximum count rate capabilities is needed. In order to overcome count rate limitations, new technological developments in reducing the size of application specific integrated circuits (ASICs) has been applied to reading out semiconductor detectors. These advancements, along with improvements to the cost and reliability of the compound semiconductor cadmium telluride (CdTe), allow us to develop a photon counting detector and read-out technology for CT. Therefore the overall goal of this Fast Track Phase I/Phase II proposal is to develop a photon counting CT detector with energy binning and read-out that is capable of producing energy resolved CT scan which can deliver less radiation dose and differentiate between tissue types.

Public Health Relevance

We are developing a fast photon counting detector for computed tomography (CT). This new technology will reduce dose and improve contrast as compared to conventional CT. The proposal submitted contains several innovative advancements to the current state of the art technologies employed in CT. This project will significantly alter the way CT scans are acquired and the dose the patient receives.

National Institute of Health (NIH)
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
Small Business Innovation Research Grants (SBIR) - Phase II (R44)
Project #
Application #
Study Section
Special Emphasis Panel (ZRG1-SBMI-T (10))
Program Officer
Lopez, Hector
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Dxray, Inc.
United States
Zip Code
Barber, W C; Wessel, J C; Nygard, E et al. (2015) Energy dispersive CdTe and CdZnTe detectors for spectral clinical CT and NDT applications. Nucl Instrum Methods Phys Res A 784:531-537
Taguchi, Katsuyuki; Iwanczyk, Jan S (2013) Vision 20/20: Single photon counting x-ray detectors in medical imaging. Med Phys 40:100901
Taguchi, Katsuyuki; Zhang, Mengxi; Frey, Eric C et al. (2011) Modeling the performance of a photon counting x-ray detector for CT: energy response and pulse pileup effects. Med Phys 38:1089-102
Taguchi, Katsuyuki; Frey, Eric C; Wang, Xiaolan et al. (2010) An analytical model of the effects of pulse pileup on the energy spectrum recorded by energy resolved photon counting x-ray detectors. Med Phys 37:3957-69
Iwanczyk, Jan S; Nygård, Einar; Meirav, Oded et al. (2009) Photon Counting Energy Dispersive Detector Arrays for X-ray Imaging. IEEE Trans Nucl Sci 56:535-542