To develop a dual-energy X-ray CT (DE-CT) system, we have performed investigation of high-speed dual-energy photon counting using two comparators and a low-dark-counting LSO-MPPC (multipixel photon counter) detector. To measure X-ray spectra, electric charges produced in the MPPC are converted into voltages and amplified by a highspeed current-voltage amplifier, and the event pulses are sent to a multichannel analyzer. The MPPC was driven under pre-Geiger mode at an MPPC bias voltage of 70.7 V. The event pulses are sent to two high-speed comparators for selecting two threshold energies to perform DE-CT. The ED-CT is accomplished by repeated linear scans and rotations of the object, and two sets of projection curves of the object are obtained simultaneously by the linear scan. In the DECT, two different-energy tomograms are obtained simultaneously, and photon-count energy subtraction imaging was carried out.

Date Published: 12 September 2014
PDF: 7 pages
Proc. SPIE 9214, Medical Applications of Radiation Detectors IV, 921405 (12 September 2014); doi: 10.1117/12.2062419

Published in SPIE Proceedings Vol. 9214:
Medical Applications of Radiation Detectors IV
H. Bradford Barber; Lars R. Furenlid; Hans N. Roehrig, Editor(s)