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

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 对于乳腺MRI，随着分辨率的提高，传统单次扫描MR的读出时间延长到 模糊和几何失真会影响图像获取。扩散加权所需的强梯度(DW) 使这一问题恶化。并行成像可以部分减少这些失真，这是最近在乳腺MRI上显示的， 使用资产。另一种方法是使用多次激发技术，如蜗牛：一种脂肪饱和的两次重新聚焦的自旋回波 具有解析设计的交错变密度螺旋读出轨迹的序列，已被应用 成功地在大脑中进行了高分辨率的DWI。我们评估了它在体内的技术可行性，用于乳房MRI，并比较 它以ASSET-DW-EPI在健康志愿者中显示ASSET-EPI和钉螺扩散加权图像。 即使使用ASSET，DW-EPI也不可能达到256x256的矩阵大小。蜗牛允许无失真采集 256x256分辨率的图像。此外，蜗牛的高分辨率和对运动的相对不敏感，允许高 高质量的多平面重新格式化与‘PET样’的对比度反转现在DWI筛查研究中流行。 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年摘要)

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)