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	Provedor de dados BJMBR (3) Autor Mejia,J. (3) Braga,J. (2) Galvis-Alonso,O.Y. (2) Leite,J.P. (2) Simões,M.V. (2) Amaro Jr,E. (1) Barboza,M.R.F. (1) Batista,I.R. (1) Bressan,R.A. (1) Castro,A.A.de (1) Chen,C.T. (1) Corrêa,R. (1) Fu,G. (1) Meng,L.J. (1) Miranda,A.C.C. (1) Reis,M.A. (1) Shih,M.C. (1) Mais... Palavra-chave Coded masks (1) Image processing (1) Instrumentation (1) Maximum likelihood (1) Mice (1) Molecular imaging (1) Multipinhole collimators (1) Pinhole collimator (1) Preclinical imaging (1) SPECT (1) Small animal SPECT (1) Small animal organs (1) Tomography (1) Mais... Tipo do documento Info:eu-repo/semantics/article (3) Ano 2013 (1) 2010 (1) 2009 (1) País Brazil (3) Idioma Inglês (3)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 3 Primeira ... 1 ... Última Performance assessment of the single photon emission microscope: high spatial resolution SPECT imaging of small animal organs BJMBR Mejia,J.; Reis,M.A.; Miranda,A.C.C.; Batista,I.R.; Barboza,M.R.F.; Shih,M.C.; Fu,G.; Chen,C.T.; Meng,L.J.; Bressan,R.A.; Amaro Jr,E.. The single photon emission microscope (SPEM) is an instrument developed to obtain high spatial resolution single photon emission computed tomography (SPECT) images of small structures inside the mouse brain. SPEM consists of two independent imaging devices, which combine a multipinhole collimator, a high-resolution, thallium-doped cesium iodide [CsI(Tl)] columnar scintillator, a demagnifying/intensifier tube, and an electron-multiplying charge-coupling device (CCD). Collimators have 300- and 450-µm diameter pinholes on tungsten slabs, in hexagonal arrays of 19 and 7 holes. Projection data are acquired in a photon-counting strategy, where CCD frames are stored at 50 frames per second, with a radius of rotation of 35 mm and magnification factor of one. The... Tipo: Info:eu-repo/semantics/article Palavras-chave: Tomography; Preclinical imaging; Molecular imaging; Mice. Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2013001100936 A clinical gamma camera-based pinhole collimated system for high resolution small animal SPECT imaging BJMBR Mejia,J.; Galvis-Alonso,O.Y.; Castro,A.A.de; Braga,J.; Leite,J.P.; Simões,M.V.. The main objective of the present study was to upgrade a clinical gamma camera to obtain high resolution tomographic images of small animal organs. The system is based on a clinical gamma camera to which we have adapted a special-purpose pinhole collimator and a device for positioning and rotating the target based on a computer-controlled step motor. We developed a software tool to reconstruct the target’s three-dimensional distribution of emission from a set of planar projections, based on the maximum likelihood algorithm. We present details on the hardware and software implementation. We imaged phantoms and heart and kidneys of rats. When using pinhole collimators, the spatial resolution and sensitivity of the imaging system depend on parameters such as... Tipo: Info:eu-repo/semantics/article Palavras-chave: Pinhole collimator; SPECT; Small animal organs; Maximum likelihood; Instrumentation; Image processing. Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2010001200004 Methodological approaches to planar and volumetric scintigraphic imaging of small volume targets with high spatial resolution and sensitivity BJMBR Mejia,J.; Galvis-Alonso,O.Y.; Braga,J.; Corrêa,R.; Leite,J.P.; Simões,M.V.. Single-photon emission computed tomography (SPECT) is a non-invasive imaging technique, which provides information reporting the functional states of tissues. SPECT imaging has been used as a diagnostic tool in several human disorders and can be used in animal models of diseases for physiopathological, genomic and drug discovery studies. However, most of the experimental models used in research involve rodents, which are at least one order of magnitude smaller in linear dimensions than man. Consequently, images of targets obtained with conventional gamma-cameras and collimators have poor spatial resolution and statistical quality. We review the methodological approaches developed in recent years in order to obtain images of small targets with good spatial... Tipo: Info:eu-repo/semantics/article Palavras-chave: Small animal SPECT; Multipinhole collimators; Coded masks. Ano: 2009 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2009000800001 Registros recuperados: 3 Primeira ... 1 ... Última

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