Compressed sensing reconstruction improves sensitivity of variable density spiral fMRI.
Magn Reson Med
; 70(6): 1634-43, 2013 Dec.
Article
em En
| MEDLINE
| ID: mdl-23390043
ABSTRACT
PURPOSE:
Functional MRI (fMRI) techniques that can provide excellent blood oxygen level dependent contrast, rapid whole brain imaging, and minimal spatial distortion are in demand. This study explored whether fMRI sensitivity can be improved through the use of compressed sensing (CS) reconstruction of variable density spiral fMRI.METHODS:
Three different CS-reconstructed 1-shot variable density spirals were explored (corresponding to 28%, 35%, and 46% under-sampling), and compared with conventional 1-shot and 2-shot Archimedean spirals acquired using matched echo time and volume repetition time. fMRI maps were reconstructed with or without CS MRI and sensitivity was compared using identically matched voxels.RESULTS:
The results demonstrated that an l1 -norm based CS reconstruction only led to an increase in functional contrast when applied to 28% under-sampled data. A whole brain t-contrast map revealed that 2-shot uniformly sampled spiral and 28% under-sampled spiral data reconstructed with CS yield equivalent sensitivity, even with matched echo time and volume repetition timeCONCLUSION:
VD spiral exhibits a useful operating range, in the region of 25-30% under-sampling, for which CS reconstruction can be used to increase the sensitivity of fMRI to brain activity. Using CS, VD acquisitions achieve the same sensitivity as 2-shot Archimedean acquisitions, but require only a single shot.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Mapeamento Encefálico
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Imageamento por Ressonância Magnética
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Interpretação de Imagem Assistida por Computador
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Aumento da Imagem
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Córtex Cerebral
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Compressão de Dados
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Potenciais Evocados
Tipo de estudo:
Diagnostic_studies
Limite:
Humans
Idioma:
En
Revista:
Magn Reson Med
Ano de publicação:
2013
Tipo de documento:
Article