PULMONARY GAS FLOW MEASUREMENT USING [3]HE MRI

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。本方案的目标是开发一种利用吸入氦3和动态MRI定量肺部气体流量的方法。这是一项发展性研究。志愿者将被3HeMRI成像。hemri是一种全新的肺成像方法，它承诺对肺功能进行高空间分辨率的评估，这是任何其他技术都无法做到的。在这个测试中，通过吸入超极化气体并形成MRI图像，可以直接看到肺空间和气道。受试者将被指示深呼吸四次，在最后一次吸气时使用3He。研究人员认为，尽可能少的吸入气体，然后是空气的“追逐者”，将会产生最好的效果。3He不会被氮气稀释。研究人员将尝试100,200和300毫升的3He剂量，以确定更大量的气体所提供的更高的噪声信号是否可以补偿更长的剂量。这将通过测量较大船只的计算流量和体积测量中的信噪比来评估。该提案的主要重点是基于评估血流的算法，开发定量方法来分析数据。研究人员已经获得了IND的批准，并打算对20名正常志愿者进行研究。这是一项初步研究，它可能会成为一种简单、无创的检查肺部气体流动的方法。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The goals of this protocol are to develop a method of quantifying pulmonary gas flow using inhalation of helium3 and dynamic MRI. This is a developmental study. Volunteers will be imaged by 3HeMRI. 3HeMRI is a radical new method of lung imaging that promises high spatial resolution assessments of lung function that are unavailable by any other technique. With this test the lung airspaces and airways are directly visualized by inhaling the hyperpolarized gas and forming MRI images. Subjects will be instructed to breathe deeply four times and on the final inhalation the 3He will be administered. The investigators believe that the smallest possible volume of inhaled gas, followed by a "chaser" of air, will give the best results. The 3He will not be diluted with nitrogen. The investigators will try doses of 100, 200 and 300 ml of 3He to determine whether the higher signal to noise offered by the greater quantity of gas compensated for the longer bolus. This will be assessed by measuring the signal to noise in calculated flow and volume measurements in the larger vessels. The main focus of the proposal is to develop quantitative methods to analyze the data, based on algorithms designed to evaluate blood flow. The investigators have an approved IND and intend to study 20 normal volunteers. This is a pilot study of what could turn out to be a simple, non-invasive way to examine pulmonary gas flow.