title: 3D weighting in cone beam image reconstruction algorithms: ray-driven vs. pixel-driven.
abstract: A 3D weighting scheme have been proposed previously to reconstruct images at both helical and axial scans in stat-of-the-art volumetric CT scanners for diagnostic imaging. Such a 3D weighting can be implemented in the manner of either ray-driven or pixel-drive, depending on the available computation resources. An experimental study is conducted in this paper to evaluate the difference between the ray-driven and pixel-driven implementations of the 3D weighting from the perspective of image quality, while their computational complexity is analyzed theoretically. Computer simulated data and several phantoms, such as the helical body phantom and humanoid chest phantom, are employed in the experimental study, showing that both the ray-driven and pixel-driven 3D weighting provides superior image quality for diagnostic imaging in clinical applications. With the availability of image reconstruction engine at increasing computational power, it is believed that the pixel-driven 3D weighting will be dominantly employed in state-of-the-art volumetric CT scanners over clinical applications.
authors.affiliation: Molecular Imaging&Computed Tomography, GE Healthcare, Waukesha, WI 53188, USA. xiangyang.tang@med.ge.com
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Tang
authors.forename: Roy A
authors.initials: RA
authors.lastname: Nilsen
authors.forename: Alex
authors.initials: A
authors.lastname: Smolin
authors.forename: Ilya
authors.initials: I
authors.lastname: Lifland
authors.forename: Dmitry
authors.initials: D
authors.lastname: Samsonov
authors.forename: Basel
authors.initials: B
authors.lastname: Taha
mesh_terms: D000465:Algorithms; D003196:Computer Graphics; D003198:Computer Simulation; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional; D015233:Models, Statistical; D008962:Models, Theoretical; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement; D013902:Radiography, Thoracic / Q000379:methods*; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*