Archimandritis, SCGiokaris, NDVarvarigou, DMaintas, DNikita, KSLoudos, GKUzunoglo, NKPapanicolas, CNThis paper investigates the possibility of developing a SPECT system that combines the high spatial resolution of position sensitive photomultiplier tubes (PSPMTs) with the excellent performance of iterative reconstruction algorithms. A small field of view (FOV) camera based on a PSPMT and a pixelized scintillation crystal made of CsI(TI) have been used for the acquisition of the projections. With the use of maximum likelihood expectation maximization (ML-EM) and ordered subsets expectation maximization (OSEM) slices of the object are obtained while three-dimensional (3D) reconstruction of the object is carried out using a modified marching cubes (MMC) algorithm. The spatial resolution of tomographic images obtained with the system was 2-3 mm. The spatial resolution of a conventional system that uses filtered backprojection (FBP) for slices reconstruction was more than 9 mm. (C) 2002 Elsevier Science Ltd. All rights reserved.http://hdl.handle.net/123456789/1533742731310.1016/S0895-6111(02)00080-0ISI:0001824701000070895-6111307engPERGAMON-ELSEVIER SCIENCE LTDComputerized Medical Imaging and GraphicscrystalHumansPosition sensitive photomultiplier tubeTomography, Emission-Computed, Single-Photonscintillation cameraSPECTImage reconstructionPhotomultipliersTomographypriority journalImaging, Three-Dimensionalalgorithmsingle photon emission computer tomographyMaximum likelihood estimationGamma Camerasimage reconstructionarticlethree dimensional imagingAlgorithmsImage Processing, Computer-AssistedCamerasIterative algorithmsPhantoms, ImagingSpatial resolutionintermethod comparisonImproving spatial resolution in SPECT with the combination of PSPMT based detector and iterative reconstruction algorithmsjournalArticle2003Ραδιολογία, Πυρηνική ιατρική και ΑπεικονιστικήRadiology, Nuclear Medicine and Imagingisi - Radiology, Nuclear Medicine & Medical Imaging covers resources on radiation research in biology and biophysics. Resources in this category focus on interventional radiology, investigative radiology, neuroradiology, radiotherapy, and oncology. Nuclear Medicine resources are concerned with the diagnostic, therapeutic, and investigative use of radionuclides. Medical Imaging resources are concerned with computerized medical imaging and graphics.Δημοσίευση σε περιοδικόPublication in journalΕπιστημονικό άρθροScientific articleΕθνικό Μετσόβιο ΠολυτεχνείοGreek Aggregator OpenArchives.gr | National Documentation Centre (EKT)other