Experiments and quantification of lumped elements volume coil for B1+ excitation at 7T
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چکیده
Introduction In an environment of ultrahigh field (UHF) MRI, B1 + inhomogeneity causes contrast difference and spatially varying image signal in region-ofinterest (ROI). Recently, several designs of radiofrequency (RF) coils have been suggested to compensate this B1 + inhomogeneity. Using parallel transmission system [1-2] is also meaning for compensating B1 + inhomogeneity. However, most of available 7T system does not have parallel transmission systems. Therefore, the finding of optimal circularly polarized (CP) volume coils with lumped element components is meaningful for compensating B1 + homogeneity. In this study, we applied four different types of volume coil (hybrid birdcage (hybrid BC), dual Helmholtz (DH), hybrid spiral birdcage (hybrid SBC), and slotted tube (ST)) for image acquisition using double-angle method (DAM) [3].
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تاریخ انتشار 2008