title: Optimization of geometrical calibration in pinhole SPECT.
abstract: Previously, we developed a method to determine the acquisition geometry of a pinhole camera. This information is needed for the correct reconstruction of pinhole single photon emission computed tomography images. The method uses a calibration phantom consisting of three point sources and their positions in the field of view (FOV) influence the accuracy of the geometry estimate. This paper proposes two particular configurations of point sources with specific positions and orientations in the FOV for optimal image reconstruction accuracy. For the proposed calibration setups, inaccuracies of the geometry estimate due to noise in the calibration data, only cause subresolution inaccuracies in reconstructed images. The calibration method also uses a model of the point source configuration, which is only known with limited accuracy. The study demonstrates, however, that, with the proposed calibration setups, the error in reconstructed images is comparable to the error in the phantom model.
authors.affiliation: Department of Nuclear Medicine, KU Leuven, 3000 Leuven, Belgium. dirk.beque@uz.kuleuven.ac.be
authors.forename: Dirk
authors.initials: D
authors.lastname: Bequé
authors.forename: Johan
authors.initials: J
authors.lastname: Nuyts
authors.forename: Paul
authors.initials: P
authors.lastname: Suetens
authors.forename: Guy
authors.initials: G
authors.lastname: Bormans
mesh_terms: D000465:Algorithms; D001185:Artificial Intelligence; D002138:Calibration; D019544:Equipment Failure Analysis / Q000379:methods; D015902:Gamma Cameras; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D009716:Numerical Analysis, Computer-Assisted; D011785:Quality Assurance, Health Care / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon / Q000295:instrumentation* / Q000379:methods*