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Calculations ofB 1 distribution, 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

  • W. Liu
  • C. M. Collins
  • M. B. Smith
Article

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 (B 1) 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 homogeneousB 1 field, 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 similarB 1 field patterns, SAR, and ISNR in all cases.

Keywords

Flip Angle Body Model Finite Difference Time Domain Finite Difference Time Domain Method Birdcage Coil 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer 2005

Authors and Affiliations

  • W. Liu
    • 1
  • C. M. Collins
    • 1
  • M. B. Smith
    • 1
    • 2
  1. 1.Center for NMR Research, NMR/MRI Building, Department of Radiology H066The Pennsylvania State University College of MedicineHersheyUSA
  2. 2.Department of Cellular and Molecular PhysiologyPennsylvania State University College of MedicineHersheyUSA

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