Advanced Quantitative Magnetic Properties Mapping of Tissue Microstructure

组织微观结构的高级定量磁特性图

• 批准号: RGPIN-2018-05047
• 负责人: Rudko, David
• 金额: $ 1.75万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=679528
• 关键词: Advanced; Quantitative; Magnetic; Properties; Mapping

Motivation***The advent of ultra high field (UHF > 3 Tesla) MRI technologies, both hardware and MRI sequence physics, has introduced the possibility of visualizing in vivo changes in human tissue structure with an unprecedented level of accuracy. Accordingly, an ultra-high resolution mapping of MRI voxel-level microstructure would be highly impactful for providing a more nuanced understanding of neurodevelopment, brain plasticity and cellular aging***This proposal aims to extend quantitative magnetic susceptibility and relaxometry-based MRI models of brain tissue microstructure to create intermediate resolution microstructure maps, based on 7 Tesla (T) MRI data. Specifically, by using an intermediate resolution of 50 150 m isotropic voxel sizes, presently achievable with 7 T animal MRI, the proposed work will seek to create reproducible assessments of myelin bilayer, axon and neuroglia magnetic susceptibility properties. MRI measurements will be related to underlying biological features by using computational models of realistic cell geometries and myelin volume fraction within an imaging voxel. ******Overall Objective***This proposal aims to formulate a reproducible, quantitative microstructure MRI method to measure both myelin volume fraction and the amount of ferritin iron stored in neuroglial cells in mouse brain. The MRI method will be developed and validated using 7 T MRI of cuprizone (CPZ)-fed mice as a highly controllable biological system for estimating myelin volume fraction and the amount ferritin iron in brain white matter.******Impact: ***While traditional MRI contrasts can reliably depict contrast in human brain tissue, they lack quantitative specificity. This is particularly relevant for MRI studies of fundamental brain neuroanatomy in basic and developmental neuroscience. A non-invasive, spatially resolved quantification of critical microstructural features in the brain would significantly enhance MRI as a tool for neurodevelopmental, neuroscience and brain aging research. Equally important, the proposed program will provide excellent training opportunities for highly qualified personnel, as well as set the basis for increased understanding of the microstructural organization of mouse brain tissue, with the ultimate goal of translating these findings/methods to human imaging.*****

动机*超高场(UHF&GT；3特斯拉)核磁共振技术的出现，无论是硬件还是核磁共振序列物理，都带来了以前所未有的精度在体内可视化人体组织结构变化的可能性。因此，MRI体素水平微结构的超高分辨率映射将对提供对神经发育、脑可塑性和细胞老化的更细微的理解具有极大的影响*本提案旨在扩展基于磁化率和驰豫测量的脑组织微结构的定量模型，以创建基于7特斯拉(T)MRI数据的中分辨率微结构图。具体地说，通过使用50 150 m各向同性体素大小的中间分辨率(目前可通过7T动物MRI实现)，拟议的工作将寻求创建可重复性的髓鞘双层、轴突和神经胶质细胞磁敏感性属性的评估。MRI测量将通过使用真实细胞几何形状和成像体素中髓鞘体积分数的计算模型来与潜在的生物学特征相关。*总体目标*本建议旨在制定一种可重复性的、定量的微结构MRI方法，以测量小鼠脑内神经胶质细胞中髓鞘体积分数和铁蛋白铁的储存数量。这种磁共振成像方法将被开发并使用7T磁共振成像(7T MRI)喂养的铜酮(CPZ)喂养的小鼠，作为一种高度可控的生物系统来估计髓鞘体积分数和脑白质中铁蛋白铁的数量。*影响：*尽管传统的MRI对比度可以可靠地描述人脑组织的对比度，但它们缺乏定量特异性。这对于基础神经科学和发育神经科学中基础脑神经解剖学的MRI研究特别相关。对大脑中的关键微结构特征进行非侵入性的空间分辨量化将大大增强MRI作为神经发育、神经科学和大脑老化研究的工具的作用。同样重要的是，拟议的计划将为高素质的人员提供极好的培训机会，并为增进对小鼠脑组织微结构组织的了解奠定基础，最终目标是将这些发现/方法转化为人类成像。