EM-IntraSPECT algorithm with ordered subsets (OSEMIS) for non-uniform attenuation correction in cardiac imaging

Published

Journal Article

Performance of the EM-IntraSPECT (EMIS) algorithm with ordered subsets (OSEMIS) for non-uniform attenuation correction in the chest was assessed. EMIS is a maximum-likelihood expectation maximization (MLEM) algorithm for simultaneously estimating SPECT emission and attenuation parameters from emission data alone. EMIS uses the activity within the patient as transmission tomography sources, with which attenuation coefficients can be estimated. However, the reconstruction time is long. The new algorithm, OSEMIS, is a modified EMIS algorithm based on ordered subsets. Emission Tc-99m SPECT data were acquired over 360° in non-circular orbit from a physical chest phantom using clinical protocol. Both a normal and a defect heart were considered. OSEMIS was evaluated in comparison to EMIS and a conventional MLEM with a fixed uniform attenuation map. Wide ranges of image measures were evaluated, including noise, log-likelihood, and region quantification. Uniformity was assessed from bull's eye plots of the reconstructed images. For the appropriate subset size, OSEMIS yielded essentially the same images as EMIS and better than MLEM, but required only one-tenth as many iterations. Consequently, adequate images were available in about fifteen iterations. © 2002 SPIE · 0277-786X/02/$15.00.

Full Text

Duke Authors

Cited Authors

  • Krol, A; Echeruo, I; Salgado, RB; Hardikar, AS; Bowsher, JE; Feiglin, DH; Thomas, FD; Lipson, E; Coman, I

Published Date

  • January 1, 2002

Published In

Volume / Issue

  • 4684 II /

Start / End Page

  • 1022 - 1027

International Standard Serial Number (ISSN)

  • 0277-786X

Digital Object Identifier (DOI)

  • 10.1117/12.467057

Citation Source

  • Scopus