7T vs. 4T: RF power, homogeneity, and signal-to-noise comparison in head images
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چکیده
منابع مشابه
7T vs. 4T: RF power, homogeneity, and signal-to-noise comparison in head images.
Signal-to-noise ratio (SNR), RF field (B(1)), and RF power requirement for human head imaging were examined at 7T and 4T magnetic field strengths. The variation in B(1) magnitude was nearly twofold higher at 7T than at 4T ( approximately 42% compared to approximately 23%). The power required for a 90 degrees pulse in the center of the head at 7T was approximately twice that at 4T. The SNR avera...
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ژورنال
عنوان ژورنال: Magnetic Resonance in Medicine
سال: 2001
ISSN: 0740-3194,1522-2594
DOI: 10.1002/mrm.1156