Methodological approaches to planar and volumetric scintigraphic imaging of small volume targets with high spatial resolution and sensitivity

Autor(es)

Mejia, J. ^[1] ; Galvis-Alonso, O. Y. ^[1] ; Braga, J. ^[2] ; Correa, R. ; Leite, J. P. ^[3] ; Simoes, M. V. ^[4]

Afiliação do(s) autor(es)

^[1] Fac Med Sao Jose do Rio Preto, Dept Biol Mol, BR-15090000 Sao Jose Do Rio Preto, SP - Brazil

^[2] Inst Nacl Pesquisas Espaciais, Div Astrofis, BR-12201 Sao Jose Dos Campos, SP - Brazil

^[3] Univ Sao Paulo, Fac Med Ribeirao Preto, Dept Neurol Psiquiatria & Psicol Med, Ribeirao Preto, SP - Brazil

^[4] Univ Sao Paulo, Fac Med Ribeirao Preto, Dept Clin Med, Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Journal of Medical and Biological Research; v. 42, n. 8, p. 692-699, AUG 2009.
• Citações Web of Science: 5

Resumo

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 resolution and sensitivity. Multipinhole, coded mask- and slit-based collimators are presented as alternative approaches to improve image quality. In combination with appropriate decoding algorithms, these collimators permit a significant reduction of the time needed to register the projections used to make 3-D representations of the volumetric distribution of target’s radiotracers. Simultaneously, they can be used to minimize artifacts and blurring arising when single pinhole collimators are used. Representation images are presented, which illustrate the use of these collimators. We also comment on the use of coded masks to attain tomographic resolution with a single projection, as discussed by some investigators since their introduction to obtain near-field images. We conclude this review by showing that the use of appropriate hardware and software tools adapted to conventional gamma-cameras can be of great help in obtaining relevant functional information in experiments using small animals. (AU)

• Processo FAPESP: 07/58052-5 - Desenvolvimento de instrumentagco e de algoritimos de processamento de dados para a producao de imagens cintilograficas de pequenos animais com resolucao espacial e temporal elevadas.
• Beneficiário: Jorge Mejía Cabeza
• Modalidade de apoio: Bolsas no Brasil - Jovens Pesquisadores
• Processo FAPESP: 07/50339-3 - Desenvolvimento de instrumentação e de algoritmos de processamento de dados para a produção de imagens cintilográficas de pequenos animais com resolução espacial e temporal elevadas
• Beneficiário: Jorge Mejía Cabeza
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 05/56447-7 - Pesquisa através de imagens por ressonância magnética de alto campo destinadas a estudos em humanos
• Beneficiário: João Pereira Leite
• Modalidade de apoio: Auxílio à Pesquisa - Programa CINAPCE - Temático