CORE PROJECT III: IMAGING OF PHYSIOLOGICAL FUNCTION

核心项目 III：生理功能成像

• 批准号: 6283131
• 负责人: EDWARD G WALSH
• 金额: $ 6.69万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-03-01 至 1999-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6283131
• 关键词: bioengineering /biomedical engineering; biomedical resource; cardiovascular system; computers; nervous system; nuclear magnetic resonance spectroscopy; technology /technique

High-field NMR imaging provides improved ability to detect small contrast changes associated with physiological function (e.g. perfusion). Techniques have been developed and implemented at 4.1T which have demonstrated improved contrast characteristics for ventricular function imaging using RF tagging. RF tagging deposits a grid of lines in the field of view at the start of the cardiac cycle which then distort as the myocardium moves across the cardiac cycle. This grid can be used in automated analysis of ventricular motion. This improvement resulted from the reduced magnetic relaxation rate at 4.1T vs clinical field strengths, the improved signal-to-noise ratio inherent at the higher field, and to radio frequency excitations developed at UAB which themselves improve tag line persistence. Animal studies have been carried out at heart rates from 75 to 130bpm demonstrating persistence of tag lines to end diastole. Myocardial perfusion has been imaged using an arterial spin-inversion technique which provides a quantitative model for perfusion estimation by comparing images in which arterial blood is magnetically inverted vs a control image. Signal differences of 1-3% have been visualized with high field imaging of animal models.

高场核磁共振成像提供了更好的能力来检测 与生理功能相关的对比变化(例如 灌流)。技术已经在4.1T开发和实施 它们表现出更好的对比度特性 使用射频标记的心功能成像。射频标记沉积a 心动周期开始时视野中的线条网格 当心肌在整个心脏周期中运动时，它就会扭曲。 该网格可用于心脏运动的自动分析。 这一改进是由于磁弛豫速率在 4.1T对比临床领域优势，改善信噪比 在较高的磁场中固有的，与射频激励有关 在UAB开发的，这本身就改善了标记行的持久性。 动物研究的心率从每分钟75到130次不等。 展示了标记线对舒张期末期的持久性。心肌 使用动脉自旋反转技术进行了血流灌注成像 它提供了一种定量模型，用于通过 比较动脉血磁性倒置的图像与 控制图像。1-3%的信号差异已被可视化 动物模型的高场成像。