READOUT MOSAIC SEGMENTED DW EPI WITH PARALLEL IMAGING AND RPGM

使用并行成像和 RPGM 读出马赛克分段 DW EPI

• 批准号: 7955361
• 负责人: SAMANTHA HOLDSWORTH
• 金额: $ 1.2万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-01 至 2010-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7955361
• 关键词: Characteristics; Computer Retrieval of Information on Scientific Projects Database; Diffusion; Funding; Grant; Image; Institution; Literature; Morphologic artifacts; Motion; Phase; Physiological; Radial; Research; Research Personnel; Resolution; Resources; Sampling; Scanning; Scheme; Source; Techniques; Technology; Time; United States National Institutes of Health; Weight; Work; improved

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Readout Mosaic Segmented DW EPI with parallel imaging and RPGM Samantha Holdsworth, Stefan Skare, Anders Nordell, Rexford Newbould, Roland Bammer The objective of this work is to improve the distortion characteristics and spatial resolution of conventional diffusion weighted EPI images. The distortions in EPI are mainly determined by the slow traversal through k-space along the phase encode direction which gives rise to blurring and geometric distortions. The short-axis propeller EPI scheme has been proposed in the literature as a robust alternative for high resolution diffusion imaging. By accelerating the k-space traversal along the phase encoding direction, distortion artifacts can be significantly diminished. Further reduction of these artifacts can be achieved when this sampling strategy is combined with parallel imaging. Similarly to FSE-Propeller, this technique also has the advantage of being inherently self navigated - whereby the center portion of k-space can be used to extract the navigator information. However, radial sampling requires N/¿ more sampling points for a given target resolution and is thus associated with a scan time penalty. Readout Mosaic Segmentation was suggested as an alternative approach for acquiring high resolution EPI images in a short scan time. With this scheme, multiple segments of k-space are acquired with a break in the readout direction. For each segment, a second EPI readout (or navigator echo) sampled in the central segment of k-space is used to correct for k-space shifts due to the presence of the DWI encoding gradients and physiological motion.

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 具有并行成像和RPGM的读出镶嵌分段DW EPI 萨曼莎·霍兹沃思、斯特凡·斯卡雷、安德斯·诺德尔、雷克斯福德·纽博尔德、罗兰·班默 这项工作的目的是改善传统的扩散加权EPI图像的失真特性和空间分辨率。EPI中的失真主要由沿相位编码方向沿着通过k空间的缓慢遍历确定，这引起模糊和几何失真。 短轴推进器EPI方案已在文献中提出作为高分辨率扩散成像的稳健替代方案。通过沿着相位编码方向加速k空间遍历，可以显著地减少失真伪影。当这种采样策略与并行成像相结合时，可以实现这些伪影的进一步减少。类似于FSE-螺旋桨，这种技术也具有固有的自我导航的优点-从而k空间的中心部分可以用于提取导航信息。然而，对于给定的目标分辨率，径向采样需要N/4个以上的采样点，并且因此与扫描时间惩罚相关联。读出镶嵌分割被建议作为在短扫描时间内获取高分辨率EPI图像的替代方法。利用该方案，k空间的多个段在读出方向上具有中断的情况下被采集。对于每个段，在k空间的中心段中采样的第二EPI读数（或导航回波）用于校正由于DWI编码梯度和生理运动的存在而引起的k空间移位。