Abstract:
:We compare two different implementations of a 3D SPECT system model for iterative reconstruction, both of which compensate for non-uniform photon attenuation and depth-dependent system response. One implementation performs fast rotation of images represented using a basis of rectangular voxels, whereas the other represents images using a basis of rotationally symmetric volume elements. In our simulations the blob-based approach was found to slightly outperform the rotation-based one in terms of the bias-variance tradeoff in the reconstructed images. Their difference can be significant, however, in terms of computational load. The rotation-based method is faster for many typical SPECT reconstruction problems, but the blob-based one can be better-suited to cases where the reconstruction algorithm needs to process one volume element at a time.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Yendiki A,Fessler JAdoi
10.1088/0031-9155/49/11/003subject
Has Abstractpub_date
2004-06-07 00:00:00pages
2157-68issue
11eissn
0031-9155issn
1361-6560journal_volume
49pub_type
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