PULMONARY GAS FLOW MEASUREMENT USING [3]HE MRI

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目及 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 本方案的目的是开发一种使用氦吸入3和动态MRI定量肺气流的方法。 这是一项发展性研究。 志愿者将通过3 HeMRI进行成像。 3 HeMRI是一种全新的肺部成像方法，它承诺对肺功能进行高空间分辨率评估，这是任何其他技术都无法实现的。 在该测试中，通过吸入超极化气体并形成MRI图像来直接可视化肺的空气空间和气道。 将指导受试者深呼吸四次，并在最后一次吸入时给予3 He。 研究人员认为，吸入尽可能小的气体，然后是空气的“追逐者”，将得到最好的结果。 3 He不会被氮气稀释。 研究人员将尝试100、200和300 ml剂量的3 He，以确定更大量气体提供的更高信噪比是否补偿了更长的推注。这将通过测量较大血管中计算的流量和体积测量值中的信噪比进行评估。 该提案的主要重点是开发定量方法来分析数据，基于旨在评估血流的算法。 研究者已获得IND批准，并计划对20名正常志愿者进行研究。这是一项初步研究，可能会成为一种简单的，非侵入性的方法来检查肺气流。

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.