HIGH-RESOLUTION, FAT-SUPPRESSED, DIFFUSION-WEIGHTED MRI OF THE BREAST

该子项目是利用资源的许多研究子项目之一 由NIH/NCRR资助的中心赠款提供。次级项目的主要支助 子项目的主要研究者可能是由其他来源提供的， 包括其他NIH来源。 列出的子项目总成本可能 表示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。 对于乳腺MRI，随着分辨率的增加，常规单次激发MR的读出时间延长到 模糊和几何失真损害图像获取。扩散加权（DW）所需的强梯度 恶化这个问题。并行成像可以部分减少这些失真，这是最近显示的乳腺MRI， 使用ASSET。另一种方法是使用多激发技术，例如SNAILS：脂肪饱和的两次重聚焦自旋回波 序列与分析设计的交错变密度螺旋读出轨迹，这已被应用 成功地在大脑中进行高分辨率DWI。我们评估其技术可行性，在身体，乳腺MRI，并比较 对健康志愿者进行ASSET-DW-EPI，显示ASSET-EPI和SNAILS弥散加权图像。 即使使用ASSET，DW-EPI在256 x256矩阵大小下也是不可能的。SNAILS允许无失真采集 256 x256分辨率图像。此外，高分辨率和相对不敏感的运动的蜗牛，允许高 高质量的多平面重建与“PET样”对比度反转，现在流行于DWI筛查研究。 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. For breast MRI, with increasing resolution the readout time for conventional single-shot MR lengthens to the point that blurring and geometric distortions impair image acquisition. The strong gradients needed for diffusion-weighting (DW) worsen this problem. Parallel imaging can partially reduce these distortions, which was recently shown for breast MRI, using ASSET. Another approach is to use a multishot technique, such as SNAILS: a fat-saturated twice-refocused spin echo sequence with an analytically designed interleaved variable-density spiral readout trajectory, which has been applied successfully to high-resolution DWI in the brain. We assess its technical feasibility in the body, for breast MRI, and compare it to ASSET-DW-EPI in healthy volunteers to show ASSET-EPI and SNAILS diffusion-weighted images. Even with ASSET, DW-EPI was not possible at a 256x256 matrix size. SNAILS allowed distortion free acquisition of 256x256 resolution images. In addition, the high resolution and relative insensitivity to motion of SNAILS, allowed for high quality multiplanar reformats with the 'PET-like' contrast-reversal now popular in DWI screening studies. To read about other projects ongoing at the Lucas Center, please visit http://rsl.stanford.edu/ (Lucas Annual Report and ISMRM 2011 Abstracts)