Title :
A study of bias for various iterative reconstruction methods in PET
Author :
Hogg, D. ; Thielemans, K. ; Mustafovic, S. ; Spinks, T.J.
Author_Institution :
Surrey Univ., Guildford, UK
Abstract :
In this work the level of positive bias in images generated by various iterative reconstructions of low activity PET data was investigated. A 3D acquisition of a low activity cylinder was performed upon an EXACT3D PET scanner followed by a multi-trial single plane simulation based upon this scan, taking into account randoms, scatter and attenuation. These were reconstructed using different implementations of maximum likelihood expectation maximisation, including the simple case of fully precorrected data and also using a separate randoms estimate with the shifted Poisson and prompts approaches. The effect of estimating the mean of randoms from the noisy delayed randoms with a maximum likelihood technique was also investigated.
Keywords :
image reconstruction; iterative methods; maximum likelihood estimation; medical image processing; positron emission tomography; 3D acquisition; EXACT3D PET scanner; bias; iterative reconstruction methods; low activity PET data; low activity cylinder; maximum likelihood expectation maximisation; multitrial single plane simulation; positron emission tomography; Attenuation; Delay effects; Delay estimation; Image generation; Image reconstruction; Iterative methods; Maximum likelihood estimation; Positron emission tomography; Reconstruction algorithms; Scattering;
Conference_Titel :
Nuclear Science Symposium Conference Record, 2002 IEEE
Print_ISBN :
0-7803-7636-6
DOI :
10.1109/NSSMIC.2002.1239610
