Lung function measured by dynamic images of 11CO, 11CO2 and 13N2

Dynamic lung images of 11CO, 11CO2 and 13N2 were used to evaluatate regional pulmonary functions. The procedures were as follows: a single breath method were used, and after a short period of breath-holding (10 -- 20 sec) the inspired gas was washed out for rebreathing room air. The images of the lung and heart were collected sequentially at 10 to 100 seconds intervals. In normal subjects, the appearance time of 11CO2 and 11CO at the heart were within 10 to 20 seconds. On the other hand in the chronic obstructive pulmonary diseases the appearance time of the both agent was prolonged. 13N2 images imediately after the inspiration showed that the well ventilated area was revealed as a region of high activity and the images at the late phase of wash out showed the distribution of the slow space. (author)