Source:http://linkedlifedata.com/resource/pubmed/id/12814590
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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
2 Pt 1
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pubmed:dateCreated |
2003-6-19
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pubmed:abstractText |
Parallel imaging methods become increasingly available on clinical MR scanners. To investigate the potential of sensitivity-encoded single-shot EPI (SENSE-EPI) for functional MRI, five imaging protocols at different SENSE reduction factors (R) and matrix sizes were compared with respect to their noise characteristics and their sensitivity toward functional activation in a motor task examination. At constant echo times, SENSE-EPI was either used to shorten the single volume acquisition times (TR(min)) at matrix size 128 x 100 (22 slices) from 3.9 s (no SENSE) to 2.0 s at R = 3, or to increase the matrix size to 192 x 153 (22 slices), resulting in TR(min) = 5.3 s for R = 2 or TR(min) = 3.4 s for R = 3. At the lower resolution, the bisection of echo train length (R = 2) substantially reduced distortions and blurring, while signal-to-noise and statistical power (measured by cluster size and maximum t value per unit time) were hardly reduced. At R = 3 the additional gain in speed and distortion reduction was quite small, while signal-to-noise and statistical power dropped significantly. With enhanced spatial resolution the time course signal-to-noise was better than expected from theory for purely thermal noise because of a reduced contribution of physiological noise, and statistical power almost reached that of the regular, low-resolution single-shot EPI, with a slight drop off toward R = 3. Thus, SENSE-EPI allows to substantially increase speed and spatial resolution in fMRI. At SENSE reduction factors up to R = 2, the potential drawbacks regarding signal-to-noise and statistical power are almost negligible.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:status |
MEDLINE
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pubmed:month |
Jun
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pubmed:issn |
1053-8119
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
19
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
412-21
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pubmed:dateRevised |
2004-11-17
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pubmed:meshHeading |
pubmed-meshheading:12814590-Adult,
pubmed-meshheading:12814590-Artifacts,
pubmed-meshheading:12814590-Brain Mapping,
pubmed-meshheading:12814590-Cerebral Cortex,
pubmed-meshheading:12814590-Echo-Planar Imaging,
pubmed-meshheading:12814590-Female,
pubmed-meshheading:12814590-Humans,
pubmed-meshheading:12814590-Image Enhancement,
pubmed-meshheading:12814590-Image Processing, Computer-Assisted,
pubmed-meshheading:12814590-Magnetic Resonance Imaging,
pubmed-meshheading:12814590-Male,
pubmed-meshheading:12814590-Mathematical Computing,
pubmed-meshheading:12814590-Motor Activity,
pubmed-meshheading:12814590-Psychomotor Performance
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pubmed:year |
2003
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pubmed:articleTitle |
Functional MRI using sensitivity-encoded echo planar imaging (SENSE-EPI).
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pubmed:affiliation |
Department of Neuroradiology, University Frankfurt, Frankfurt, Germany. preibisch@em.uni-frankfurt.de
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pubmed:publicationType |
Journal Article
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