Journal of Biomedical Engineering Research (대한의용생체공학회:의공학회지)

The Korean Society of Medical and Biological Engineering (대한의용생체공학회)
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RF Shimming Considering Coupling Effects for High-Field MRI

  • Heo, Hye-Young (Department of Biomedical Engineering, Kyung Hee University) ;
  • Cho, Min-Hyoung (Department of Biomedical Engineering, Kyung Hee University) ;
  • Lee, Soo-Yeol (Department of Biomedical Engineering, Kyung Hee University)
  • Published : 2008.08.30
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Abstract

The RF shimming technique has been used to improve the transmit RF field homogeneity in highfield MRI. In the RF shimming technique, the amplitude and phase of the driving currents in each coil element are optimized to get homogenous flip angle or uniform image intensity. The inductive and capacitive coupling between the coil elements may degrade the RF field homogeneity if not taken into account in the optimization procedure. In this paper, we have analyzed the coupling effects on the RF shimming using a sixteen-element TEM RF coil model operating at 300 MHz. We have found that the coupling effects on the RF shimming can be reduced by putting high dielectric material between the active rung and the shield.

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References

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