Proton MRI to measure lung ventilation and perfusion

描述（由申请人提供）：与计算机断层扫描和核医学技术等其他成像方式相比，人类肺部的定量功能磁共振成像（MRI）相对较差。这些MRI技术不受暴露于电离辐射或造影剂注射的限制，因此为无限的重复研究打开了大门，并提供了新领域的可能性，如时间成像。该计划的长期目标是开发和建立定量功能质子MRI在人类肺部作为一种现成的手段，提供局部信息的灌注，通气和气体交换是生理和临床相关的。我们开发的技术使我们能够定量测量肺密度（空气含量的直接测量），肺血流量和特定的空间分布。 通风.这些技术使我们能够定量地绘制通气灌注比 （V？A/Q？），其以接近于人肺的功能性气体交换单元的尺度的空间分辨率唯一地确定肺气体交换。生物工程研究伙伴关系（BRP）前五年的总体目标是使这些研究技术可转化为更广泛的研究社区，以便它们可以在研究和临床试验中用作生物标志物，未来的目标是临床适用性。a）加强其生理学解释，为解释其产生的结果提供严格的基础; B）进一步发展为临床研究的有效和可获得的技术;以及c）进行验证研究，以证明其适用于临床研究。为了这些目的，我们提出了一系列协调的研究，将：1）使用高度解剖现实的计算机模拟模型，将所有成像模式的生理解释置于合理的基础上; 2）通过与临床前大型动物模型中注射和吸入微球测量值进行比较，验证灌注、通气和VA/Q的成像; 3）在正常肺和患病肺中，用从多惰性气体消除技术的金标准非成像方法获得的VA/Q的定量测量交叉验证人中VA/Q的成像; 4）优化现有的MR方法学，用改进的技术扩大肺功能成像的范围。本BRP的完成将产生一套可访问的经确认的定量功能MR肺成像方法的可交付成果，用于市售扫描仪，以测量密度、灌注、通气和通气-灌注比。

DESCRIPTION (provided by applicant): In comparison to other imaging modalities such as computerized tomography and nuclear medicine techniques, quantitative functional magnetic resonance imaging (MRI) of the human lung is relatively poorly developed. These MRI techniques are not limited by exposure to ionizing radiation or contrast injection and thus open the door to unlimited repeated studies, and offer the possibility of new fields such as temporal imaging. The long-term objective of this program is to develop and establish quantitative functional proton MRI in the human lung as a readily available means of providing regional information on perfusion, ventilation and gas exchange that is physiologically and clinically relevant. Techniques we have developed allow us to quantitatively measure the spatial distributions of lung density (a direct measure of air content), pulmonary blood flow, and specific ventilation. Together these techniques permit us to quantitatively map ventilation- perfusion ratio (V? A/Q?), which uniquely determines pulmonary gas exchange, with a spatial resolution that is close to the scale of the functional gas exchange unit of the human lung. The overall goal of the first five years of this Bioengineering Research Partnership (BRP) is to make these research techniques translatable to the wider research community so that they may be used as biomarkers in research studies and in clinical trials, with a future goal of clinical applicability To do so, these techniques need to: a) have their physiological interpretation strengthened to provide a rigorous basis for interpretation of the results they produce; b) be further developed into efficient and accessible techniques for clinical studies; and c) be subjected to validation studies to prove their applicability for clinical studies. To these ends we propose a coordinated series of studies that will: 1) use highly anatomically-realistic in-silico modeling to place the physiological interpretation of all imaging modalities on a sound footing; 2) validate imaging of perfusion, ventilation and V A/Q by comparing with injected and inhaled microsphere measurements in a pre-clinical large animal model; 3) cross- validate imaging of V A/Q in humans with quantitative measures of VA/Q obtained from the gold-standard non-imaging approach of the multiple inert gas elimination technique, both in the normal and diseased lung; and 4) optimize the current MR methodology and expand the repertoire of functional lung imaging with improved techniques. Completion of this BRP will result in deliverables of an accessible suite of validated quantitative functional MR lung imaging methods for use on commercially available scanners to measure density, perfusion, ventilation, and ventilation-perfusion ratio.