Evaluation of 3D reconstruction algorithms for a small animal PET camera

The use of paired, opposing position-sensitive phototube scintillation cameras (SCs) operating in coincidence for small animal imaging with positron emitters is currently under study. Because of the low sensitivity of the system even in 3D mode and the need to produce images with high resolution, it was postulated that a 3D expectation maximization (EM) reconstruction algorithm might be well suited for this application. The authors investigated six reconstruction algorithms for the 3D SC PET camera: 2D filtered back-projection (FBP), 3D reprojection (3DRP), 2D EM, 3D EM, 2D ordered subset EM (OSEM), and 3D OSEM. Noise was assessed for all slices by the coefficient of variation in a simulated uniform cylinder. Resolution was assessed from a simulation of 15 point sources in the warm background of the uniform cylinder. At comparable noise levels, the resolution achieved with EM and OSEM (0.9-mm to 1.2-mm) is significantly better than that obtained with FBP or 3DRP (1.5-mm to 2.0-mm.) Images of a rat skull labeled with /sup 18/F-fluoride suggest that 3D EM and 3D OSEM can improve image quality of a small animal PET camera.

[1]  T. Jones,et al.  2D and 3D imaging of small animals and the human radial artery with a high resolution detector for PET , 1992 .

[2]  S. Strother,et al.  Practical tradeoffs between noise, quantitation, and number of iterations for maximum likelihood-based reconstructions. , 1991, IEEE transactions on medical imaging.

[3]  P M Bloomfield,et al.  PET scanners for small animals. , 1995, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[4]  P E Kinahan,et al.  Figures of merit for comparing reconstruction algorithms with a volume-imaging PET scanner. , 1994, Physics in medicine and biology.

[5]  Richard E. Carson,et al.  Precision and accuracy of regional radioactivity quantitation using the maximum likelihood EM reconstruction algorithm , 1994, IEEE Trans. Medical Imaging.

[6]  Yuchen Yan,et al.  A system for the 3D reconstruction of retracted-septa PET data using the EM algorithm , 1995 .

[7]  Michael V. Green,et al.  Characteristics of a pair of small field-of-view LSO scintillation cameras , 1996 .

[8]  S C Strother,et al.  Noise and signal decoupling in maximum likelihood reconstructions and Metz filters for PET images , 1992, IEEE Conference on Nuclear Science Symposium and Medical Imaging.

[9]  Jeih-San Liow,et al.  Improved resolution via 3D iterative reconstruction for PET volume imaging , 1994, Proceedings of 1994 IEEE Nuclear Science Symposium - NSS'94.

[10]  Richard E. Carson,et al.  Noise characteristics of 3-D and 2-D PET images , 1998, IEEE Transactions on Medical Imaging.

[11]  T J Spinks,et al.  The design and physical characteristics of a small animal positron emission tomograph. , 1995, Physics in medicine and biology.

[12]  T. Lewellen,et al.  Dynamic high resolution imaging of rats: quantitative potentials , 1991, Conference Record of the 1991 IEEE Nuclear Science Symposium and Medical Imaging Conference.

[13]  Paul Kinahan,et al.  Analytic 3D image reconstruction using all detected events , 1989 .

[14]  Alvaro R. De Pierro,et al.  A row-action alternative to the EM algorithm for maximizing likelihood in emission tomography , 1996, IEEE Trans. Medical Imaging.

[15]  H. Malcolm Hudson,et al.  Accelerated image reconstruction using ordered subsets of projection data , 1994, IEEE Trans. Medical Imaging.