Development of MRI scan methods to image inhaled fluorocarbon gases as biomarkers of lung structure and function.

该项目的目的是开发新的磁共振成像（MRI）方法来测量肺的功能和结构特性。我们将对全氟丙烷在肺部的分布进行成像，全氟丙烷是一种惰性的可吸入气体，可以通过19F-MRI进行可视化：一种MRI扫描，可以检测吸入的全氟丙烷气体中的氟核。我们将实施和测试新的MRI扫描仪硬件和扫描采集方法，以提高使用该方法进行肺部扫描的图像质量，并使用加速扫描方法来提高呼吸系统疾病患者的扫描耐受性。虽然在目前的临床实践中有评估肺结构和功能特性的方法，但这些方法要么缺乏空间信息（因此无法检测与早期呼吸系统疾病相关的细微局部变化），要么使用对患者有风险的电离辐射。MRI提供了一种安全、可重复、无辐射的成像方法，我们的肺成像方法允许定量测量肺通气特性，而不是对呼吸系统疾病敏感。该项目开发的新型医疗技术将支持肺部19F-MRI临床研究和临床实践的下游应用。本研究的主要目标是测量MRI加速方法对肺通气特性19F-MRI测量的影响，并将加速19F-MRI方法应用于肺功能和结构测量的发展，最终应用于临床研究和临床实践。我们假设，结合先进的加速技术可以显著提高扫描分辨率，缩短扫描时间，从而提高对呼吸系统疾病患者通气缺陷的量化能力，并提供更好、更方便患者的扫描方法（如自由呼吸扫描，而不是屏气扫描）。MRI扫描加速方法在常规临床MRI扫描中得到了很好的应用。加速方法，如平行成像和压缩传感，是所有主要MRI扫描仪制造商的产品，然而，它们在多核MRI（如吸入全氟丙烷的19F-MRI）中的应用并不广泛，也不容易在标准临床扫描仪上实现。我们认识到，现有的肺19F-MRI方法尚未充分利用扫描加速方法提供的功能，我们看到肺19F-MRI图像质量的显著改善超出了目前的技术水平。我们的研究将使用肺部模拟测试对象和健康志愿者的研究来测试新的MRI扫描仪传感器（RF线圈）硬件和扫描仪软件（MRI脉冲序列）。我们将结合并行成像和压缩传感，生成更详细（更高分辨率）的肺通气特性3D图像，并从静态肺图像推进到动态（电影）3D图像，显示整个肺部示踪气体的洗入和洗出。该项目开发的新成像技术将立即用于评估呼吸系统疾病进展的临床研究，以及评估治疗策略（例如新药物治疗）对肺功能的影响，并且成像方法有可能朝着在临床实践中用于呼吸系统疾病诊断和监测的最终目标发展。

The aim of this project is to develop new magnetic resonance imaging (MRI) methods to measure lung functional and structural properties. We will image the distribution within the lung of perfluoropropane - an inert, inhalable gas that can be visualised with 19F-MRI: an MRI scan that detects the fluorine nuclei within inhaled perfluoropropane gas. We will implement and test new MRI scanner hardware and scan acquisition methods to improve the image quality of lung scans made with this method, and use accelerate scan methods to improve scan tolerability for patients with respiratory disorders. Whilst there are methods to assess lung structural and functional properties in current clinical practice, these either lack spatial information (and so don't detect subtle localised changes associated with early respiratory disease) or use ionising radiation that carries a risk to the patient. MRI offers a safely repeatable and radiation-free imaging method and our approach to lung imaging permits quantitative measurement of lung ventilation properties than is sensitive to respiratory disease.The novel healthcare technologies developed in this project will underpin the downstream use of lung 19F-MRI clinical research and clinical practice.Project objectivesThe key objectives of this study are to measure the impact of MRI acceleration methods on 19F-MRI measures of lung ventilation properties, and to employ accelerated 19F-MRI methods in the development of lung functional and structural measurements than can ultimately be applied in clinical research and clinical practice. We hypothesise that a combination of advanced acceleration techniques can deliver a marked improvement in scan resolution and reduced scan duration, which in turn can improve ability to quantify ventilation defects in patients with respiratory disease and deliver better and more patient-friendly scan methods (such as free-breathing rather than breath-held scanning).MRI scan acceleration methods are well established for conventional clinical MRI scanning. Acceleration methods such as parallel imaging and compressed sensing are available as products from all major MRI scanner manufacturers, however their use in multinuclear MRI (such as 19F-MRI of inhaled perfluoropropane) is not widespread or easily implemented on a standard clinical scanner. We recognise that existing lung 19F-MRI methods have not yet fully exploited the capabilities provided by scan acceleration methods, and we see scope for significant improvement of image quality for lung 19F-MRI beyond the current state of the art. Our studies will use lung-mimicking test objects and studies of healthy volunteers to test new MRI scanner sensor (RF coil) hardware and scanner software (MRI pulse sequences). We will combine parallel imaging and compresses sensing to produce more detailed (higher resolution) 3D images of lung ventilation properties and advance from static lung images to dynamic (movie) 3D images that show the wash-in and wash-out of our tracer gases throughout the lungs. The new imaging technologies developed in this project will then be positioned for immediate use in clinical research studies that assess the progression of respiratory diseases, and that assess the effects of therapeutic strategies (e.g. novel drug treatments) on lung function, and the imaging methods have potential for development towards the ultimate goal of use in clinical practice for respiratory disease diagnosis and monitoring.