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

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 7 T MR扫描仪提供了更高的空间分辨率，增加的光谱分离以及增强的成像质量。 对比度 不幸的是，在7 T下的几个技术问题，如B1不均匀性和SAR增加，导致信号丢失 并且当使用常规成像序列时限制了空间覆盖。 表观T2值也有效地 对于单回波序列，在1000场强下减少。 常规Shinnar Le-Roux（SLR）180？脉冲用于 自旋回波序列对B1不均匀性非常敏感。 可以使用绝热180 <$脉冲代替SLR脉冲 以提供B1不敏感的重新聚焦。 要了解卢卡斯中心正在进行的其他项目，请访问http://rsl.stanford.edu/ （卢卡斯年度报告和 ISMRM 2011摘要）

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)