Development andApplication of Methodology of Magnetic Resonance Measurement of Hyperpolarized Noble Gas Contributable to Physiological Diagnosis.

本研究成功地研制出一种超极化氙气(HPXe)连续流产生器，其灵敏度可提高约2万倍。将Hp Xe MRI应用于肺成像，建立了同时进行Hp Xe肺功能成像和脑内松弛速率测量的方法学，并探讨了COPD小鼠模型肺功能和脑松弛速度的关系。结果显示肺功能局部异常，T1I-1较健康小鼠升高。T1I-1与肺内气体交换百分率呈负相关。

The continuous-flow type apparatus for producing hyperpolarized xenon (HP Xe) which can improve the sensitivity by ca. 20,000 times has been successfully developed in the present study. Adopting HP Xe MRI to the lungimaging, we developed the methodology to simultaneously perform the pulmonary functional imaging and the relaxation rate measurement in the brain of HP Xe and investigated the relationship between the two functions of the mouse models of COPD. As a result, the regional abnormalities of the pulmonary funation could be visualized, and the T1i-1was increased compared to that of the healthy mouse. A negative correlation between the T1i-1and the % gas-exchange in the lung was observed.