title: Calculations ofB1Distribution, Specific Energy Absorption Rate, and Intrinsic Signal-to-Noise Ratio for a Body-Size Birdcage Coil Loaded with Different Human Subjects at 64 and 128 MHz.
abstract: A numerical model of a female body is developed to study the effects of different body types with different coil drive methods on radio-frequency magnetic (B1) field distribution, specific energy absorption rate (SAR), and intrinsic signal-to-noise ratio (ISNR) for a body-size birdcage coil at 64 and 128 MHz. The coil is loaded with either a larger, more muscular male body model (subject 1) or a newly developed female body model (subject 2), and driven with two-port (quadrature), four-port, or many (ideal) sources. Loading the coil with subject 1 results in significantly less homogeneousB1field, higher SAR, and lower ISNR than those for subject 2 at both frequencies. This dependence of MR performance and safety measures on body type indicates a need for a variety of numerical models representative of a diverse population for future calculations. The different drive methods result in similarB1field patterns, SAR, and ISNR in all cases.
authors.affiliation: Department of Radiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA.
authors.forename: W
authors.initials: W
authors.lastname: Liu
authors.forename: C M
authors.initials: CM
authors.lastname: Collins
authors.forename: M B
authors.initials: MB
authors.lastname: Smith
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