Dynamic MRI for Myrocardial Perfusion and Viability

用于心肌灌注和活力的动态 MRI

• 批准号: 6847747
• 负责人: EDWARD VR DIBELLA
• 金额: $ 22.43万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-07 至 2007-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6847747
• 关键词: angiocardiography; bioimaging /biomedical imaging; blood flow measurement; clinical research; computer assisted diagnosis; contrast media; coronary disorder; diagnosis design /evaluation; diagnosis quality /standard; heart disorder diagnosis; heart imaging /visualization /scanning; human subject; image enhancement; magnetic resonance imaging; noninvasive diagnosis; patient oriented research; perfusion; positron emission tomography

DESCRIPTION (provided by applicant): This proposal seeks to improve the accuracy of noninvasive diagnosis and prognosis of coronary artery disease by using MRI and a gadolinium-based paramagnetic contrast agent. First-pass MRI with the modeling methods proposed here may be able to provide absolute regional blood flows at a high spatial resolution. These first-pass studies may also offer unique viability information. The specific aims are (1) To develop and optimize acquisition strategies to obtain data tailored for compartmental modeling (2) To develop clinically practical methods for analyzing the cardiac contrast MRI data with models (3) To compare the flow estimates from the MRI methods developed here to an MRI upslope perfusion index and to absolute blood flow measurements obtained with dynamic N-13-ammonia PET. (4) To add viability measures from the first pass modeling approach to delayed images to determine if such an approach improves prediction of viability. Methods: (1) Systematic analysis of temporal sampling strategies and the use of reduced k-space acquisitions to increase volume coverage, reduce artifacts, and maintain signal and high spatial resolution will be pursued using realistic computer simulations and human studies. (2) Linked active contours combined with temporal clustering methods will be developed to automatically segment the endocardium and epicardium in the time series data. Methods for blind identification of the input function (input functions are inaccurate at high gadolinium concentrations) will be developed and validated. Two different physiological models will be developed and compared in their ability to provide absolute flow values and reliable extracellular volume estimates. (3) The comparisons with MRI upslope and PET perfusion will be performed using 34 human studies. (4) The first-pass viability measures and three integrated viability measures will be compared to delayed enhancement Gd MRI images and to post-revascularization data in 17 patients. The outcome of this project will be validated imaging protocols and software for use with first-passMRI studies, and practical and accurate methods for myocardial perfusion and viability assessment in vivo. Such methods will be invaluable for improved health care and for improved basic science research, such as tracking nascent flow changes in gene therapy.

描述(由申请人提供)： 这项建议旨在通过使用MRI和一种基于Gd的顺磁造影剂来提高冠状动脉疾病的无创性诊断和预后的准确性。采用本文提出的建模方法的首过磁共振成像可能能够以高空间分辨率提供绝对的区域血流。这些首次通过的研究也可能提供独特的生存信息。其具体目标是(1)开发和优化采集策略，以获得为分区建模量身定做的数据(2)开发用于分析心脏对比MRI数据的临床实用方法和模型(3)将本文开发的MRI方法的流量估计值与MRI上坡血流指数以及动态N-13-氨PET获得的绝对血流量测量结果进行比较。(4)将第一遍建模方法中的生存能力度量添加到延迟图像中，以确定这种方法是否提高了生存能力的预测。方法：(1)利用真实的计算机模拟和人体研究，对时间采样策略进行系统分析，并使用减少的k空间采集来增加体积覆盖、减少伪影、保持信号和高空间分辨率。(2)将链接活动轮廓线与时间聚类法相结合，自动分割时间序列数据中的心内膜和心外膜。将开发和验证输入函数的盲辨识方法(输入函数在高Gd浓度时不准确)。将开发两种不同的生理模型，并比较它们提供绝对流量值和可靠的细胞外体积估计的能力。(3)在34项人体研究中，将与MRI上坡法和PET灌注法进行比较。(4)将17例患者的首过生存能力指标和三项综合生存能力指标与延迟增强的Gd MRI图像和血管重建后的数据进行比较。该项目的成果将是用于首次通过MRI研究的经过验证的成像方案和软件，以及用于活体心肌灌注和存活评估的实用和准确的方法。这些方法将对改善医疗保健和改善基础科学研究，如跟踪基因治疗中新生的流动变化，具有无价的价值。