SELF-REFOCUSED ADIABATIC PULSE FOR SPIN ECHO IMAGING AT 7T

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This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. 7T MR scanners offer the advantages of higher spatial resolution, increased spectral separation as well as enhanced contrast. Unfortunately, several technical issues at 7T, such as B1 inhomogeneity and increased SAR, result in signal loss and limit the spatial coverage when using conventional imaging sequences. Apparent T2 values are also effectively reduced for single echo sequences at ultrahigh field strengths. Conventional Shinnar Le-Roux (SLR) 180¿ pulses used in spin-echo sequences are highly susceptible to B1 inhomogeneity. Adiabatic 180¿ pulses may be used instead of SLR pulses in spin echo sequences to provide B1-insensitive refocusing. To read about other projects ongoing at the Lucas Center, please visit http://rsl.stanford.edu/ (Lucas Annual Report and ISMRM 2011 Abstracts)