High-flip-angle slice-selective parallel RF transmission with 8 channels at 7T
نویسندگان
چکیده
منابع مشابه
High-flip-angle slice-selective parallel RF transmission with 8 channels at 7 T.
At high magnetic field, B(1)(+) non-uniformity causes undesired inhomogeneity in SNR and image contrast. Parallel RF transmission using tailored 3D k-space trajectory design has been shown to correct for this problem and produce highly uniform in-plane magnetization with good slice selection profile within a relatively short excitation duration. However, at large flip angles the excitation k-sp...
متن کاملHigh flip angle slice selective Parallel RF Excitation on an 8-channel system at 3T
K. Setsompop, A. C. Zelinski, V. A. Alagappan, U. J. Fontius, F. Hebrank, F. Schmitt, L. L. Wald, and E. Adalsteinsson EECS, Massachusetts Institute of Technology, Cambridge, MA, United States, A. A. Martinos Center for Biomedical Imaging, MGH, Harvard Medical School, Charlestown, MA, United States, Siemens Medical Solutions, Erlangen, Germany, Siemens Medical Solutions, Charlestown, MA, United...
متن کاملHigh-Speed RF Modulation System for 32 Parallel Transmission Channels at 7T
Introduction: Higher field strengths in MRI are well known for their potential to increase image resolution due to higher signal-to-noise ratio (SNR). However, due to the high dielectric permittivity of human tissue and higher resonance frequencies, and thus shorter wavelengths on the order of the human body size, RF interference artifacts are likely to occur. To overcome these constraints, par...
متن کاملHigh‐resolution gradient‐recalled echo imaging at 9.4T using 16‐channel parallel transmit simultaneous multislice spokes excitations with slice‐by‐slice flip angle homogenization
PURPOSE In order to fully benefit from the improved signal-to-noise and contrast-to-noise ratios at 9.4T, the challenges of B1+ inhomogeneity and the long acquisition time of high-resolution 2D gradient-recalled echo (GRE) imaging were addressed. THEORY AND METHODS Flip angle homogenized excitations were achieved by parallel transmission (pTx) of 3-spoke pulses, designed by magnitude least-sq...
متن کاملGain of Imaging Fidelity by Employing a Higher Number of Independent Transmit Channels Together with Slice-Selective Radio-Frequency (RF) Shimming at 7T
Dielectric resonance effects and radio-frequency (RF) power deposition have become challenging issues for magnetic resonance imaging at ultrahigh-field (UHF) strengths. The use of transmit (Tx) coil arrays with independently-driven RF sources using a parallel transmission system is a promising method for alleviating the resulting RF inhomogeneities. In this study, the effect on homogeneity and ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Magnetic Resonance
سال: 2008
ISSN: 1090-7807
DOI: 10.1016/j.jmr.2008.08.012