title: A multi-source inverse-geometry CT system: initial results with an 8 spot x-ray source array.
abstract: We present initial experimental results of a rotating-gantry multi-source inverse-geometry CT (MS-IGCT) system. The MS-IGCT system was built with a single module of 2 × 4 x-ray sources and a 2D detector array. It produced a 75 mm in-plane field-of-view (FOV) with 160 mm axial coverage in a single gantry rotation. To evaluate system performance, a 2.5 inch diameter uniform PMMA cylinder phantom, a 200 µm diameter tungsten wire, and a euthanized rat were scanned. Each scan acquired 125 views per source and the gantry rotation time was 1 s per revolution. Geometric calibration was performed using a bead phantom. The scanning parameters were 80 kVp, 125 mA, and 5.4 µs pulse per source location per view. A data normalization technique was applied to the acquired projection data, and beam hardening and spectral nonlinearities of each detector channel were corrected. For image reconstruction, the projection data of each source row were rebinned into a full cone beam data set, and the FDK algorithm was used. The reconstructed volumes from upper and lower source rows shared an overlap volume which was combined in image space. The images of the uniform PMMA cylinder phantom showed good uniformity and no apparent artifacts. The measured in-plane MTF showed 13 lp cm(-1) at 10% cutoff, in good agreement with expectations. The rat data were also reconstructed reliably. The initial experimental results from this rotating-gantry MS-IGCT system demonstrated its ability to image a complex anatomical object without any significant image artifacts and to achieve high image resolution and large axial coverage in a single gantry rotation.
authors.affiliation: School of Integrated Technology, 205 Science Engineering and Pharmacy Hall, Yonsei University, 406-840 Incheon, Korea.
authors.forename: Jongduk
authors.initials: J
authors.lastname: Baek
authors.forename: Bruno
authors.initials: B
authors.lastname: De Man
authors.forename: Jorge
authors.initials: J
authors.lastname: Uribe
authors.forename: Randy
authors.initials: R
authors.lastname: Longtin
authors.forename: Daniel
authors.initials: D
authors.lastname: Harrison
authors.forename: Joseph
authors.initials: J
authors.lastname: Reynolds
authors.forename: Bogdan
authors.initials: B
authors.lastname: Neculaes
authors.forename: Kristopher
authors.initials: K
authors.lastname: Frutschy
authors.forename: Louis
authors.initials: L
authors.lastname: Inzinna
authors.forename: Antonio
authors.initials: A
authors.lastname: Caiafa
authors.forename: Robert
authors.initials: R
authors.lastname: Senzig
authors.forename: Norbert J
authors.initials: NJ
authors.lastname: Pelc
mesh_terms: D000465:Algorithms; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008029:Lighting / Q000295:instrumentation*; D061330:Multidetector Computed Tomography / Q000295:instrumentation*; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000295:instrumentation* / Q000379:methods*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity