Abstract:
:In this paper, Novikov's inversion formula of the attenuated two-dimensional (2D) Radon transform is applied to the reconstruction of attenuated fan-beam projections acquired with equal detector spacing and of attenuated cone-beam projections acquired with a flat planar detector and circular trajectory. The derivation of the fan-beam algorithm is obtained by transformation from parallel-beam coordinates to fan-beam coordinates. The cone-beam reconstruction algorithm is an extension of the fan-beam reconstruction algorithm using Feldkamp-Davis-Kress's (FDK) method. Computer simulations indicate that the algorithm is efficient and is accurate in reconstructing slices close to the central slice of the cone-beam orbit plane. When the attenuation map is set to zero the implementation is equivalent to the FDK method. Reconstructed images are also shown for noise corrupted projections.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Huang Q,Zeng GL,You J,Gullberg GTdoi
10.1088/0031-9155/50/10/010subject
Has Abstractpub_date
2005-05-21 00:00:00pages
2329-39issue
10eissn
0031-9155issn
1361-6560pii
S0031-9155(05)94836-7journal_volume
50pub_type
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