dc.contributor |
Universitat de Barcelona |
dc.contributor.author |
Aguiar, Pablo |
dc.contributor.author |
Pino Sorroche, Francisco |
dc.contributor.author |
Silva-Rodríguez, Jesús |
dc.contributor.author |
Pavía Segura, Javier |
dc.contributor.author |
Ros Puig, Domènec |
dc.contributor.author |
Ruibal Morell, Álvaro |
dc.contributor.author |
El Bitar, Ziad |
dc.date |
2017-06-28T09:19:22Z |
dc.date |
2017-06-28T09:19:22Z |
dc.date |
2014-03-03 |
dc.date |
2017-06-28T09:19:22Z |
dc.identifier.citation |
0094-2405 |
dc.identifier.citation |
646907 |
dc.identifier.uri |
http://hdl.handle.net/2445/112996 |
dc.format |
10 p. |
dc.format |
application/pdf |
dc.language.iso |
eng |
dc.publisher |
American Association of Physicists in Medicine |
dc.relation |
Reproducció del document publicat a: https://doi.org/10.1118/1.4866380 |
dc.relation |
Medical Physics, 2014, vol. 41, num. 3, p. 32501 |
dc.relation |
https://doi.org/10.1118/1.4866380 |
dc.rights |
(c) American Association of Physicists in Medicine, 2014 |
dc.rights |
info:eu-repo/semantics/openAccess |
dc.subject |
Algorismes |
dc.subject |
Simulació per ordinador |
dc.subject |
Mètode de Montecarlo |
dc.subject |
Programari |
dc.subject |
Tomografia computada per emissió de fotó simple |
dc.subject |
Algorithms |
dc.subject |
Computer simulation |
dc.subject |
Monte Carlo method |
dc.subject |
Computer software |
dc.subject |
Single-photon emission computed tomography |
dc.title |
Analytical, experimental, and Monte Carlo system response matrix for pinhole SPECT reconstruction |
dc.type |
info:eu-repo/semantics/article |
dc.type |
info:eu-repo/semantics/publishedVersion |
dc.description.abstract |
PURPOSE: To assess the performance of two approaches to the system response matrix (SRM) calculation in pinhole single photon emission computed tomography (SPECT) reconstruction. METHODS: Evaluation was performed using experimental data from a low magnification pinhole SPECT system that consisted of a rotating flat detector with a monolithic scintillator crystal. The SRM was computed following two approaches, which were based on Monte Carlo simulations (MC-SRM) and analytical techniques in combination with an experimental characterization (AE-SRM). The spatial response of the system, obtained by using the two approaches, was compared with experimental data. The effect of the MC-SRM and AE-SRM approaches on the reconstructed image was assessed in terms of image contrast, signal-to-noise ratio, image quality, and spatial resolution. To this end, acquisitions were carried out using a hot cylinder phantom (consisting of five fillable rods with diameters of 5, 4, 3, 2, and 1 mm and a uniform cylindrical chamber) and a custom-made Derenzo phantom, with center-to-center distances between adjacent rods of 1.5, 2.0, and 3.0 mm. RESULTS: Good agreement was found for the spatial response of the system between measured data and results derived from MC-SRM and AE-SRM. Only minor differences for point sources at distances smaller than the radius of rotation and large incidence angles were found. Assessment of the effect on the reconstructed image showed a similar contrast for both approaches, with values higher than 0.9 for rod diameters greater than 1 mm and higher than 0.8 for rod diameter of 1 mm. The comparison in terms of image quality showed that all rods in the different sections of a custom-made Derenzo phantom could be distinguished. The spatial resolution (FWHM) was 0.7 mm at iteration 100 using both approaches. The SNR was lower for reconstructed images using MC-SRM than for those reconstructed using AE-SRM, indicating that AE-SRM deals better with the projection noise than MC-SRM. CONCLUSIONS: The authors' findings show that both approaches provide good solutions to the problem of calculating the SRM in pinhole SPECT reconstruction. The AE-SRM was faster to create and handle the projection noise better than MC-SRM. Nevertheless, the AE-SRM required a tedious experimental characterization of the intrinsic detector response. Creation of the MC-SRM required longer computation time and handled the projection noise worse than the AE-SRM.Nevertheless, the MC-SRM inherently incorporates extensive modeling of the system and therefore experimental characterization was not required. |