Three-dimensional mapping of brain venous oxygenation using R2* oximetry.
Magn Reson Med
; 79(3): 1304-1313, 2018 03.
Article
em En
| MEDLINE
| ID: mdl-28585238
ABSTRACT
PURPOSE:
Cerebral venous oxygenation (Yv ) is an important biomarker for brain diseases. This study aims to develop an R2*-based MR oximetry that can measure cerebral Yv in 3D.METHODS:
This technique separates blood signal from tissue by velocity-encoding phase contrast and measures the R2* of pure blood by multi-gradient-echo acquisition. The blood R2* was converted to Yv using an R2*-versus-oxygenation (Y) calibration curve, which was obtained by in vitro bovine blood experiments. Reproducibility, sensitivity, validity, and resolution dependence of the technique were evaluated.RESULTS:
In vitro R2*-Y calibration plot revealed a strong dependence of blood R2* on oxygenation, with additional dependence on hematocrit. In vivo results demonstrated that the technique can provide a 3D venous oxygenation map that depicts both large sinuses and smaller cortical veins, with venous oxygenation ranging from 57 to 72%. Intrasession coefficient of variation of the measurement was 3.0%. The technique detected an average Yv increase of 10.8% as a result of hyperoxia, which was validated by global oxygenation measurement from T2 -Relaxation-Under-Spin-Tagging (TRUST) MRI. Two spatial resolutions, one with an isotropic voxel dimension and the other with a nonisotropic dimension, were tested for full brain coverage.CONCLUSIONS:
This study demonstrated the feasibility of 3D brain oxygenation mapping without using contrast agent. Magn Reson Med 791304-1313, 2018. © 2017 International Society for Magnetic Resonance in Medicine.Palavras-chave
Texto completo:
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Encéfalo
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Mapeamento Encefálico
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Oximetria
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Circulação Cerebrovascular
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Angiografia por Ressonância Magnética
Limite:
Adult
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Female
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Humans
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Male
Idioma:
En
Revista:
Magn Reson Med
Ano de publicação:
2018
Tipo de documento:
Article