López-Montes, AlejandroGalve, PabloUdias Moinelo, José ManuelCal-González, JacoboVaquero López, Juan JoséDesco Menéndez, ManuelHerraiz, Joaquín L.2020-11-252020-11-252020-04-19Applied sciences, 10(8), 2829, April 2020, 18 pp.2076-3417https://hdl.handle.net/10016/31480Real-time positron emission tomography (PET) may provide information from first-shot images, enable PET-guided biopsies, and allow awake animal studies. Fully-3D iterative reconstructions yield the best images in PET, but they are too slow for real-time imaging. Analytical methods such as Fourier back projection (FBP) are very fast, but yield images of poor quality with artifacts due to noise or data incompleteness. In this work, an image reconstruction based on the pseudoinverse of the system response matrix (SRM) is presented. w. To implement the pseudoinverse method, the reconstruction problem is separated into two stages. First, the axial part of the SRM is pseudo-inverted (PINV) to rebin the 3D data into 2D datasets. Then, the resulting 2D slices can be reconstructed with analytical methods or by applying the pseudoinverse algorithm again. The proposed two-step PINV reconstruction yielded good-quality images at a rate of several frames per second, compatible with real time applications. Furthermore, extremely fast direct PINV reconstruction of projections of the 3D image collapsed along specific directions can be implemented.18eng© 2020 by the authors. Licensee MDPI, Basel, Switzerland.This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) licenseAtribución 3.0 EspañaPositron emission tomographyRebinningReal-timeImage reconstructionSystemMatrixPseudoinverseresearch articleBiología y Biomedicinahttps://doi.org/10.3390/APP10082829open access18, 282918Applied Sciences10AR/0000025676