title: Initial results from a prototype whole-body photon-counting computed tomography system.
abstract: X-ray computed tomography (CT) with energy-discriminating capabilities presents exciting opportunities for increased dose efficiency and improved material decomposition analyses. However, due to constraints imposed by the inability of photon-counting detectors (PCD) to respond accurately at high photon flux, to date there has been no clinical application of PCD-CT. Recently, our lab installed a research prototype system consisting of two x-ray sources and two corresponding detectors, one using an energy-integrating detector (EID) and the other using a PCD. In this work, we report the first third-party evaluation of this prototype CT system using both phantoms and a cadaver head. The phantom studies demonstrated several promising characteristics of the PCD sub-system, including improved longitudinal spatial resolution and reduced beam hardening artifacts, relative to the EID sub-system. More importantly, we found that the PCD sub-system offers excellent pulse pileup control in cases of x-ray flux up to 550 mA at 140 kV, which corresponds to approximately 2.5×1011photons per cm2per second. In an anthropomorphic phantom and a cadaver head, the PCD sub-system provided image quality comparable to the EID sub-system for the same dose level. Our results demonstrate the potential of the prototype system to produce clinically-acceptable imagesin vivo.
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, MN, USA 55905.
authors.forename: Z
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, MN, USA 55905.
authors.forename: S
authors.initials: S
authors.lastname: Leng
authors.affiliation: Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA 55905.
authors.forename: S M
authors.initials: SM
authors.lastname: Jorgensen
authors.affiliation: Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA 55905.
authors.forename: Z
authors.initials: Z
authors.lastname: Li
authors.affiliation: Siemens Medical Solutions, Malvern, PA, USA 19355.
authors.forename: R
authors.initials: R
authors.lastname: Gutjahr
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, MN, USA 55905.
authors.forename: B
authors.initials: B
authors.lastname: Chen
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, MN, USA 55905.
authors.forename: X
authors.initials: X
authors.lastname: Duan
authors.affiliation: Siemens Medical Solutions, Malvern, PA, USA 19355.
authors.forename: A F
authors.initials: AF
authors.lastname: Halaweish
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, MN, USA 55905.
authors.forename: L
authors.initials: L
authors.lastname: Yu
authors.affiliation: Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA 55905.
authors.forename: E L
authors.initials: EL
authors.lastname: Ritman
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, MN, USA 55905.
authors.forename: C H
authors.initials: CH
authors.lastname: McCollough
keywords: Photon-Counting CT; Research Prototype; System Evaluation