RT Journal Article
T1 Tissue-dependent and spatially-variant positron range correction in 3D PET
A1 Cal González, Jacobo
A1 Pérez Liva, Mailyn
A1 López Herraiz, Joaquín
A1 Vaquero, Juan José
A1 Desco, Manuel
A1 Udías Moinelo, José Manuel
AB Positron range (PR) is a significant factor that limits PET image resolution, especially with some radionuclides currently used in clinical and preclinical studies such as (82)Rb, (124)I and (68)Ga. The use of an accurate model of the PR in the image reconstruction may minimize its impact on the image quality. Nevertheless, PR distributions are difficult to model, as they may be different at each voxel and direction, depending on the materials that the positron flies through. Several approximated methods have been proposed, considering only one or several propagating media without taking into account boundaries effects. In some regions, like lungs or trachea, these methods may not be accurate enough and yield artifacts. In this work, we present an efficient method to accurately incorporate spatially-variant PR corrections. The method is based on pre-computing voxel-dependent PR kernels using a CT or a manually segmented image, and a model of the dependence of the PR on each material derived from Monte Carlo simulations. The images are convoluted with these kernels in the forward-projection step of the iterative reconstruction algorithm. This implementation of the algorithm adds a modest overhead to the overall reconstruction time and it obtains artifact-free PR-corrected images, even when the activity is concentrated at tissue boundaries with extreme changes of density. We verified the method with the preclinical Argus PET/CT scanner, but it can be also applied to other scanners and improve the image quality in clinical PET studies using isotopes with large PR.
PB IEEE
SN 0278-0062
YR 2015
FD 2015-05-22
LK https://hdl.handle.net/20.500.14352/131193
UL https://hdl.handle.net/20.500.14352/131193
LA eng
NO J. Cal-Gonzalez, M. Perez-Liva, J. L. Herraiz, J. J. Vaquero, M. Desco, and J. M. Udias, “Tissue-Dependent and Spatially-Variant Positron Range Correction in 3D PET,” IEEE Trans. Med. Imaging, vol. 34, no. 11, pp. 2394–2403, Nov. 2015.
NO © 2015 IEEE
DS Docta Complutense
RD 25 mar 2026