HIGH FIELD MRI: LIMITATIONS AND SOLUTIONS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 这项研究的目标是了解并开发工程解决方案，以解决在高磁场强度下磁共振成像(MRI)所面临的困难。最近在明尼苏达大学举行的一次关于高场MRI的研讨会(1999)最近确定了磁化率引起的信号损失、射频磁场失真和信噪比是高场实施面临的三个最紧迫的问题。我们的伙伴关系将直接解决其中两个重要问题。具体目标1：开发和验证方法学，以分析、量化并最终消除高场磁共振图像中因磁化率区域差异而产生的静态磁场失真。这些解决方案将用于开发用于高速功能磁共振成像和人体、动物和细胞解剖的无失真磁共振成像的无失真校正技术。具体目标2：开发和验证模型和方法，以分析和量化人体头部和身体中发生的射频(RF)磁场失真。这些解决方案将用于评估吸收的射频能量对患者的安全性，以及评估射频场均匀度及其潜在校正的失真和限制。本着生物工程研究伙伴关系的精神，这项建议将吸收来自明尼苏达大学磁共振研究中心(首次亮相的7.0Tesla全身MRI国家研究资源中心)、Remcom(一家磁场建模软件公司)和国家高场磁场实验室(一家包含14特斯拉MRI显微镜的国家研究实验室)的专业知识和合作伙伴关系。这些研究的结果将在高速无失真功能MRI、低场强和高场强下的解剖学研究、动物和完整细胞中的MR显微镜、患者安全性评估以及在许多情况下被证明在高场强下存在问题的回收技术方面为广泛的研究人员提供帮助。

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. he objective of this research is to understand and develop engineering solutions to the difficulties presented to magnetic resonance imaging (MRI) at high magnetic field strength. A recent workshop at the University of Minnesota (1999) on high field MRI recently identified magnetic susceptibility induced signal loss, radio frequency magnetic field distortion, and signal-to-noise as the three most pressing issues facing high field implementation. Our partnership will directly address two of these important issues. Specific Aim 1: Develop and validate methodology to analyze, quantify, and ultimately elimiate static magnetic field distortion produced in high field MR images by regional differences in magnetic susceptibility. These solutions will be used to develop distortion-free correction techniques for high-speed functional MRI and distortion-free MRI of human, animal, and cellular anatomy. Specific Aim 2: Develop and validate models and methodology to analyze, and quantify radio frequency (rf) magnetic field distortion occurring in the human head and body. These solutions will be used to evaluate patient safety from absorbed rf energy and to evaluate distortion and limitations of rf field homogeneity and its potential correction. In the spirit of the Bioengineering Research Partnership this proposal will draw expertise and partnership from the Center for Magnetic Resonance Research at the University of Minnesota (a premiere 7.0 Tesla whole body MRI National Research Resource Center), REMCOM (a magnetiac field modeling software company), and the National High FIeld Magnet Laboratory (a National Research Laboratory incorporating 14 Tesla MRI microscopy). The results of these studies will aid a wide array of researchers in high speed distortion-free functional MRI, aanatomical studies at both low and high field strengths, MR microscopy in animals and intact cells, evaluation of patient safety, and in many cases reclaiming techniques which have proven problematic at high field strengths.