RFOV DW/ZONAL OBLIQUE MULTISLICE (ZOOM) COMBINED/READOUT-SEGMENTED (RS)-EPI

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 子项目的主要研究者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。 使用回波平面成像（EPI）的弥散加权成像（DWI）受到几何失真和模糊的限制， 特别是在具有大的非共振效应的区域中 组织/空气界面。EPI中的几何失真也与相位编码方向（FOVpe）上的FOV成比例 作为EPI序列中相邻回波之间的回波间隔（Tro）。为了减少FOVpe并避免混叠，这里我们使用 区域倾斜多层EPI（ZOOM-EPI）技术，它使用倾斜的重聚焦脉冲。为了进一步减少失真，Tro 可以通过用一系列连续的段或“盲”覆盖k空间来减少，称为RS-EPI。这里我们 实现了ZOOM脉冲与RS-EPI轨迹（ZOOM-RS-EPI），以获得两种方法的优点， 减少失真。

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. Diffusion-weighted imaging (DWI) using echo-planar imaging (EPI) has been limited by geometric distortion and blurring, particularly in regions with large off-resonance effects such as in the spinal-cord and in regions of the brain residing near tissue/air interfaces. Geometric distortion in EPI is proportional to the FOV in the phase encoding direction (FOVpe), as well as the echo-spacing between adjacent echoes in the EPI train (Tro). To reduce FOVpe and avoid aliasing, here we use the zonal oblique multislice EPI (ZOOM-EPI) technique, which uses a tilted refocusing pulse. To reduce distortion further, Tro can be reduced by covering k-space with a series of consecutive segments or 'blinds', known as RS-EPI. Here we implemented the ZOOM pulse together with the RS-EPI trajectory (ZOOM-RS-EPI) to get the benefits of both methods for reducing distortion.