Determination of optimal collimation parameters for a rotating slat collimator system: a system matrix method using ML-EM.
Fiche publication
Date publication
mars 2016
Journal
Physics in medicine and biology
Auteurs
Membres identifiés du Cancéropôle Est :
Dr BRASSE David
Tous les auteurs :
Boisson F, Bekaert V, Brasse D
Lien Pubmed
Résumé
Nowadays, Single Photon imaging has become an essential part of molecular imaging and nuclear medicine. Whether to establish a diagnosis or in the therapeutic monitoring, this modality presents performance that continues to improve. For over 50 years, several collimators have been proposed. Mainly governed by collimation parameters, the resolution-sensitivity trade-off is the factor determining the collimator the most suitable for an intended study. One alternative to the common approaches is the rotating slat collimator (RSC). In the present study, we are aiming at developing a preclinical system equipped with a RSC dedicated to mice and rats imaging, which requires both high sensitivity and spatial resolution. We investigated the resolution-sensitivity trade-offs obtained by varying different collimation parameters: (i) the slats height (H), and (ii) the gap between two consecutive slats (g), considering different intrinsic spatial resolutions. One system matrix was generated for each set of collimation parameters (H,g). Spatial resolutions, Signal-to-Noise Ratio (SNR) and sensitivity obtained for all the set of collimation parameters (H,g) were measured in the 2D projections reconstructed with ML-EM. According to our results, 20 mm high slats and a 1 mm gap were chosen as a good RSC candidate for a preclinical detection module. This collimator will ensure a sensitivity greater than 0.2% and a system spatial resolution below 1 mm, considering an intrinsic spatial resolution below 0.8 mm.
Mots clés
Algorithms, Animals, Mice, Phantoms, Imaging, Photons, Rats, Signal-To-Noise Ratio, Tomography, Emission-Computed, Single-Photon, instrumentation
Référence
Phys Med Biol. 2016 Mar;61(6):2302-18