Title :
Characterization of the modulation transfer function of discrete filtered backprojection
Author :
Glick, Stephen J. ; King, Michael A. ; Penney, Bill C.
Author_Institution :
Dept. of Nucl. Med., Massachusetts Univ., Med. Center, Worcester, MA, USA
fDate :
6/1/1989 12:00:00 AM
Abstract :
A mathematical expression for the modulation transfer function (MTF) of image reconstruction by discrete filtered backprojection (DFBP) is derived. A simulation study is used to investigate the dependence of the MTF of DFBP on: (1) the number of projection views; (2) the type of ramp filter used; (3) the interpolation method used during backprojection; and (4) the position of the object. These results were compared to MTFs calculated from point-source single-photon-emission computed tomographic (SPECT) acquisitions in air. The experimentally obtained MTFs contained much of the same structure as the MTFs of DFBP obtained through simulation. It is shown that the discretization of the filtered backprojection process can cause the tomographic transfer function to be anisotropic and nonstationary. However, through proper selection of the methods used in reconstruction, a nearly isotropic and stationary MTF can be obtained
Keywords :
computerised tomography; radioisotope scanning and imaging; discrete filtered backprojection; image reconstruction; interpolation method; mathematical expression; modulation transfer function; projection views; single-photon-emission computerised tomography; Degradation; Electromagnetic scattering; Filtering; Filters; Image reconstruction; Image restoration; Optical computing; Particle scattering; Single photon emission computed tomography; Transfer functions;
Journal_Title :
Medical Imaging, IEEE Transactions on