MULTI-ECHO PHASE-BASED FAT/WATER SEPARATION

基于多回波相位的脂肪/水分离

• 批准号: 7358789
• 负责人: WENXIAO LU
• 金额: $ 0.94万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-06-01 至 2007-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7358789
• 关键词: MULTI; ECHO; PHASE; BASED; FAT

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. Introduction: Fat suppression is crucial to numerous clinical applications of MRI, including cardiovascular, abdominal and musculoskeletal imaging. In previous work, partially supported by this research resource, investigators have developed a robust iterative reconstruction technique, ¿IDEAL,¿ to separate water from fat using several MR images with different echo times resulting in different phase difference between fat and water signals. Initial clinical evaluation of IDEAL has been successful. However, the technique can benefit from scan time reduction, and improved efficiency, which are both goals of the present work. Methods and Discussion: IDEAL (Iterative Decomposition of water and fat with Echo Asymmetry and Least squares estimation) is a robust algorithm for separation of water and fat using images with at least 3 different echo times. Normally, a full acquisition is used for each echo time. In this work we use a multi-echo readout, that acquires data for all three echo times in a single acquisition. This reduces total scan time by about a factor of two, without reducing SNR significantly, and improves robustness to patient motion. We have applied this technique to musculoskeletal imaging to produce a sub-five-minute 3D cartilage imaging sequence, and to 3D liver imaging, which enables imaging within a breath-hold. Results show excellent fat/water separation in most cases, though as the echo spacing increases, there are cases where the fat/water swaps occur. Future work will involve improving the robustness of the reconstruction as the echo spacing increases, allowing higher resolution imaging. We will also apply this technique to rapid cardiac imaging, where motion makes the standard IDEAL technique difficult.

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。前言：脂肪抑制对于MRI的许多临床应用是至关重要的，包括心血管、腹部和肌肉骨骼成像。在之前的工作中，研究人员在这一研究资源的部分支持下，开发了一种健壮的迭代重建技术？理想，使用几个具有不同回波时间的MR图像来分离水和脂肪，从而导致脂肪和水信号之间的不同相位差。IDEAD的初步临床评估是成功的。然而，该技术可以受益于扫描时间的减少和效率的提高，这两个都是本工作的目标。方法和讨论：理想(回声不对称和最小二乘估计的水和脂肪的迭代分解)是一种使用至少3个不同回波时间的图像来分离水和脂肪的稳健算法。正常情况下，每个回波时间都使用完全捕获。在这项工作中，我们使用多回波读数，即在一次采集中采集所有三个回波时间的数据。这将总扫描时间减少了大约1/2，而不会显著降低SNR，并提高了对患者运动的稳健性。我们已经将这项技术应用到肌肉骨骼成像中，以产生不到5分钟的3D软骨成像序列，并应用到3D肝脏成像中，这使得成像能够在屏气的情况下进行。结果表明，大多数情况下脂肪/水分离良好，但随着回声间隔的增加，也有发生脂肪/水交换的情况。未来的工作将包括随着回波间隔的增加而提高重建的稳健性，从而实现更高分辨率的成像。我们还将把这项技术应用于快速心脏成像，其中运动使标准的理想技术变得困难。