Bastein Guérin1, Georges El Fakhri. 1. B. Guérin is with the University of Paris VI, 75006 Paris, France and also with Harvard University, Cambridge, MA 02138 USA. (e-mail: guerin@pet.mgh.harvard.edu ).
Abstract
We have developed and validated a realistic simulation of random coincidences, pixelated block detectors, light sharing among crystal elements and dead-time in 2D and 3D positron emission tomography (PET) imaging based on the SimSET Monte Carlo simulation software. Our simulation was validated by comparison to a Monte Carlo transport code widely used for PET modeling, GATE, and to measurements made on a PET scanner. METHODS: We have modified the SimSET software to allow independent tracking of single photons in the object and septa while taking advantage of existing voxel based attenuation and activity distributions and validated importance sampling techniques implemented in SimSET. For each single photon interacting in the detector, the energy-weighted average of interaction points was computed, a blurring model applied to account for light sharing and the associated crystal identified. Detector dead-time was modeled in every block as a function of the local single rate using a variance reduction technique. Electronic dead-time was modeled for the whole scanner as a function of the prompt coincidences rate. Energy spectra predicted by our simulation were compared to GATE. NEMA NU-2 2001 performance tests were simulated with the new simulation as well as with SimSET and compared to measurements made on a Discovery ST (DST) camera. RESULTS: Errors in simulated spatial resolution (full width at half maximum, FWHM) were 5.5% (6.1%) in 2D (3D) with the new simulation, compared with 42.5% (38.2%) with SimSET. Simulated (measured) scatter fractions were 17.8% (21.3%) in 2D and 45.8% (45.2%) in 3D. Simulated and measured sensitivities agreed within 2.3 % in 2D and 3D for all planes and simulated and acquired count rate curves (including NEC) were within 12.7% in 2D in the [0: 80 kBq/cc] range and in 3D in the [0: 35 kBq/cc] range. The new simulation yielded significantly more realistic singles' and coincidences' spectra, spatial resolution, global sensitivity and lesion contrasts than the SimSET software.
We have developed and validated a realistic simulation of random coincidences, pixelated block detectors, light sharing among crystal elements and dead-time in 2D and 3D positron emission tomography (PET) imaging based on the SimSET Monte Carlo simulation software. Our simulation was validated by comparison to a Monte Carlo transport code widely used for PET modeling, GATE, and to measurements made on a PET scanner. METHODS: We have modified the SimSET software to allow independent tracking of single photons in the object and septa while taking advantage of existing voxel based attenuation and activity distributions and validated importance sampling techniques implemented in SimSET. For each single photon interacting in the detector, the energy-weighted average of interaction points was computed, a blurring model applied to account for light sharing and the associated crystal identified. Detector dead-time was modeled in every block as a function of the local single rate using a variance reduction technique. Electronic dead-time was modeled for the whole scanner as a function of the prompt coincidences rate. Energy spectra predicted by our simulation were compared to GATE. NEMA NU-2 2001 performance tests were simulated with the new simulation as well as with SimSET and compared to measurements made on a Discovery ST (DST) camera. RESULTS: Errors in simulated spatial resolution (full width at half maximum, FWHM) were 5.5% (6.1%) in 2D (3D) with the new simulation, compared with 42.5% (38.2%) with SimSET. Simulated (measured) scatter fractions were 17.8% (21.3%) in 2D and 45.8% (45.2%) in 3D. Simulated and measured sensitivities agreed within 2.3 % in 2D and 3D for all planes and simulated and acquired count rate curves (including NEC) were within 12.7% in 2D in the [0: 80 kBq/cc] range and in 3D in the [0: 35 kBq/cc] range. The new simulation yielded significantly more realistic singles' and coincidences' spectra, spatial resolution, global sensitivity and lesion contrasts than the SimSET software.
Authors: S Jan; G Santin; D Strul; S Staelens; K Assié; D Autret; S Avner; R Barbier; M Bardiès; P M Bloomfield; D Brasse; V Breton; P Bruyndonckx; I Buvat; A F Chatziioannou; Y Choi; Y H Chung; C Comtat; D Donnarieix; L Ferrer; S J Glick; C J Groiselle; D Guez; P F Honore; S Kerhoas-Cavata; A S Kirov; V Kohli; M Koole; M Krieguer; D J van der Laan; F Lamare; G Largeron; C Lartizien; D Lazaro; M C Maas; L Maigne; F Mayet; F Melot; C Merheb; E Pennacchio; J Perez; U Pietrzyk; F R Rannou; M Rey; D R Schaart; C R Schmidtlein; L Simon; T Y Song; J M Vieira; D Visvikis; R Van de Walle; E Wieërs; C Morel Journal: Phys Med Biol Date: 2004-10-07 Impact factor: 3.609
Authors: Xiaoli Li; Adam M Alessio; Thompson H Burnett; Thomas K Lewellen; Roberts Miyaoka Journal: IEEE Trans Nucl Sci Date: 2013-06 Impact factor: 1.679
Authors: Georges El Fakhri; Cathryn M Trott; Arkadiusz Sitek; Ali Bonab; Nathaniel M Alpert Journal: Mol Imaging Biol Date: 2013-12 Impact factor: 3.488