PT Journal
AU Rodriguez-Alvarez, MJ
   Sanchez, F
   Soriano, A
   Iborra, A
   Mora, C
TI Exploiting symmetries for weight matrix design in CT imaging
SO Mathematical and Computer Modelling
JI Math. Comput. Model.
PY 2011
BP 1655
EP 1664
VL 54
IS 7-8
DI 10.1016/j.mcm.2010.12.004
LA English
DE Computerized tomography imaging; Polar grid; System matrix; Rotation symmetries; ART
AB In this paper we propose several methods of constructing the system matrix (SM) of a Computed Tomography (CT) scanner with two objectives: (1) to construct SMs in the shortest possible time and store them in an ordinary PC without losing quality, (2) to analyze the possible applications of the proposed method to 3D, taking into account SMs' sizes, computing time and reconstructed image quality. In order to build the SM, we propose two new field of view (FOV) pixellation schemes, based on a polar coordinate system (polar grid) by taking advantage of the polar rotation symmetries of CT devices. Comparisons between the SMs proposed are performed using two phantom and a real CT-simulator images. Global error, contrast, noise and homogeneity of the reconstructed images are discussed.
ER