Development of Airway Imaging Using HP 3He MRI

使用 HP 3He MRI 开发气道成像

• 批准号: 7501714
• 负责人: MITCHELL S ALBERT
• 金额: $ 59.67万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-15 至 2010-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7501714
• 关键词: asthma; bioimaging /biomedical imaging; biomedical equipment development; clinical research; computed axial tomography; helium; human subject; lung; lung imaging /visualization /scanning; magnetic resonance imaging; methacholine; patient oriented research; pulmonary respiration; respiratory function

DESCRIPTION (provided by applicant): Historically, lung ventilation has been difficult to image. Although other imaging modalities provide insight into airway anatomy and reactivity (e.g., MDCT) or ventilation (e.g., dynamic CT, radio-nuclear imaging including PET), to date only CT can combine a view of both structure and function. However, the associated radiation, particularly in children, is driving a search for alternative methodologies. The unique work of our group forms an essential part of this effort to limit radiation exposure while improving our ability to depict the structural and functional mechanics of lung ventilation. To this end, we propose to establish HP 3He MRI as a clinically safe imaging modality that enables us to visualize ventilation function and airway constriction. However, a number of challenges regarding our ability to quantitate structure and function using this modality remain. As imaging moves into the arena of quantitative regional functional assessment of the lung, our drive to establish HP 3He MRI as an acceptable alternative or as a complimentary modality to current CT technologies could not be better timed. We further propose to combine HP 3He MRI with sensitive measures of airway function to determine the specific constriction conditions associated with asthma. We will test the hypothesis that HP 3He MRI provides similar airway resolution to MDCT, as well as additional functional ventilation information. This will entail 1) optimizing our current dynamic HP 3He MRI methodology to obtain high-resolution images of the airways; 2) developing both airway and ventilation quantification methods for the HP 3He MR images; 3) calculating HP 3He MRI airway diameters for both healthy and asthmatic subjects; and 4) comparing these measurements to those obtained from MDCT lung imaging and 3D airway reconstruction. We will then test the hypothesis that airway constriction in asthmatics is highly heterogeneous and is primarily characterized by airway closures in the small airways, and that airway dilation during a deep inspiration is diminished with increased asthma severity. Specifically, we will systematically investigate the distinctive nature of pulmonary airway narrowing and expansion in healthy versus asthmatic lungs both pre- and post-methacholine challenge using hyperpolarized (HP) 3He MRI and, as an overarching objective, discern its implication for the diagnosis and treatment of asthma. We will also investigate the frequency dependence of dynamic lung resistance and elastance and calculate the airway resistance during both normal breathing and a deep inspiration. Finally, we will correlate structural defects in airway constriction and ventilation with functional defects. At a minimum, successful proof-of-concept will establish HP 3He MRI as an important complement to MDCT. Indeed, by offering both functional information as well as a degree of airway resolution comparable to MDCT, all without the need for radiation exposure, we are confident the use HP 3He MRI will ultimately lead to improved asthma management across the spectrum--from diagnosis to treatment to enhanced quality of life.

描述（由申请人提供）： 从历史上看，肺通气很难成像。尽管其他成像方式可以深入了解气道解剖结构和反应性（例如 MDCT）或通气（例如动态 CT、包括 PET 在内的放射性核成像），但迄今为止，只有 CT 可以结合结构和功能的视图。然而，相关的辐射，尤其是儿童的辐射，正在推动寻找替代方法。我们小组的独特工作构成了限制辐射暴露的努力的重要组成部分，同时提高了我们描述肺通气的结构和功能机制的能力。为此，我们建议将 HP 3He MRI 作为一种临床安全的成像方式，使我们能够可视化通气功能和气道收缩。然而，我们使用这种方式定量结构和功能的能力仍然存在许多挑战。随着成像进入肺部定量区域功能评估领域，我们将 HP 3He MRI 作为可接受的替代方案或作为当前 CT 技术的补充模式的努力恰逢其时。 我们进一步建议将 HP 3He MRI 与气道功能的敏感测量相结合，以确定与哮喘相关的特定收缩情况。我们将检验 HP 3He MRI 提供与 MDCT 类似的气道分辨率以及附加功能性通气信息的假设。这将需要 1) 优化我们当前的动态 HP 3He MRI 方法，以获得高分辨率的气道图像； 2) 开发 HP 3He MR 图像的气道和通气量化方法； 3) 计算健康受试者和哮喘受试者的 HP 3He MRI 气道直径； 4) 将这些测量值与 MDCT 肺部成像和 3D 气道重建获得的测量值进行比较。然后，我们将检验以下假设：哮喘患者的气道收缩具有高度异质性，其主要特征是小气道的气道关闭，并且深吸气期间的气道扩张随着哮喘严重程度的增加而减弱。 具体来说，我们将使用超极化 (HP) 3He MRI 系统地研究健康肺与哮喘肺在乙酰甲胆碱激发前和后肺气道狭窄和扩张的独特性质，并作为总体目标，了解其对哮喘诊断和治疗的影响。我们还将研究动态肺阻力和弹性的频率依赖性，并计算正常呼吸和深吸气期间的气道阻力。最后，我们将气道收缩和通气的结构缺陷与功能缺陷联系起来。 至少，成功的概念验证将使 HP 3He MRI 成为 MDCT 的重要补充。事实上，通过提供功能信息以及与 MDCT 相当的气道分辨率，所有这些都不需要辐射暴露，我们相信 HP 3He MRI 的使用最终将改善整个范围的哮喘管理——从诊断到治疗，再到提高生活质量。

项目成果

Marked pericardial inhomogeneity of specific ventilation at total lung capacity and beyond.

总肺容量及以上的比通气量明显心包不均匀。

• DOI: 10.1016/j.resp.2009.07.024
• 发表时间: 2009
• 期刊: Respiratory physiology & neurobiology
• 影响因子: 2.3
• 作者: Sun,Yanping;Butler,JamesP;Lindholm,Peter;Walvick,RonnP;Loring,StephenH;Gereige,Jessica;Ferrigno,Massimo;Albert,MitchellS
• 通讯作者: Albert,MitchellS