High-Res Multishot DTI by Real-Time Navigation

通过实时导航实现高分辨率多镜头 DTI

• 批准号: 7140284
• 负责人: EUN-KEE (E.K.) JEONG
• 金额: $ 16.88万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2008-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7140284
• 关键词: bioimaging /biomedical imaging; brain imaging /visualization /scanning; brain stem; clinical research; diffusion magnetic resonance imaging; heart imaging /visualization /scanning; human subject; neuroimaging; optic nerve; peripheral nervous system; spinal cord imaging /visualization; technology /technique development; time resolved data

DESCRIPTION (provided by applicant): Diffusion Tensor (DT) MRI provides unique information about the microscopic mobility of the water molecules in tissues that cannot be obtained with any other medical imaging technique. Diffusion weighted imaging (DWI) has become a powerful routine tool for detecting regions of cell edema in cerebral stroke. DT-MRI is generally used to examine the tracts of myelinated nerves for various white-matter diseases in the brain. However, conventional DT-MRI techniques are very sensitive to magnetic susceptibility artifacts, and cannot achieve very high spatial resolution. There is a substantial need for high-resolution DT-MRI techniques that work in difficult areas such as the optic nerves, brainstem, peripheral nerves, and spinal cord, as well as in the heart and some other organs. Multi-shot DT-MRI techniques could be used to increase spatial resolution and overcome susceptibility artifacts, but are very sensitive to phase errors due to microscopic motions during the large diffusion gradients. This project will complete the development and perform a detailed evaluation of a novel technique for robust high resolution multi-shot DT-MRI. The technique is novel in that it acquires both components of the diffusion prepared magnetization in conjunction with a single diffusion weighting and thereby eliminates non-uniform diffusion weighting due to residual phase in the diffusion weighted transverse magnetization. A navigator echo provides a measure of data quality and allows artifact reduction by dynamic data re-acquisition. For brevity, we refer to the technique as 2D or 3D nav-CADPaW-EPI (navigated composite acquisition of diffusion prepared and weighted magnetization using multi-shot EPI). After successful development, optimization, and testing of the pulse sequence, we will perform a detailed study of the accuracy, repeatability, and anatomic consistency of the resulting DT measurements in the brain, brain stem, optic nerve, and spinal cord. The technique can also be applied to any anatomic region where the susceptibility artifact is severe. The technique developed and tested in this project should ultimately improve the ability to detect early MS lesions in the optic nerve and spinal cord and provide finer detail for white matter tractography uniformly over the entire brain and nervous system.

描述(由申请人提供)： 扩散张量(DT)磁共振成像提供了有关组织中水分子微观流动性的独特信息，这是任何其他医学成像技术无法获得的。弥散加权成像(DWI)已成为检测脑卒中细胞水肿区的有力常规工具。DT-MRI通常用于检查大脑中各种白质疾病的有髓神经束。然而，传统的DT-MRI技术对磁化率伪影非常敏感，不能达到很高的空间分辨率。对高分辨率的DT-MRI技术有很大的需求，这种技术可以在困难的区域工作，如视神经、脑干、周围神经和脊髓，以及心脏和其他一些器官。多次激发DT-MRI技术可用于提高空间分辨率和克服磁化率伪影，但对大扩散梯度过程中的微观运动引起的相位误差非常敏感。 该项目将完成开发，并对一种新的技术进行详细的评估，以实现稳健的高分辨率多激发DT-MRI。该技术是新颖的，因为它结合单一扩散加权获得了扩散准备磁化的两个分量，从而消除了由于扩散加权横向磁化中的残余相而导致的不均匀扩散加权。导航仪回波提供了数据质量的度量，并允许通过动态数据重新采集来减少伪影。为简洁起见，我们将该技术称为2D或3D NAV-CADPaW-EPI(使用多次激发EPI进行扩散准备和加权磁化的导航复合采集)。在成功开发、优化和测试脉冲序列后，我们将对脑、脑干、视神经和脊髓的DT测量结果的准确性、可重复性和解剖学一致性进行详细研究。该技术还可应用于敏感性伪影严重的任何解剖区域。在该项目中开发和测试的技术最终将提高检测视神经和脊髓中早期MS病变的能力，并为整个大脑和神经系统统一的白质纤维束成像提供更精细的细节。