The origin of the pulmonary densitometric pulse
M. J. Raphael, R. E. Steiner, Richard H. Greenspan · British Journal of Radiology · 1969
1. Two groups of experiments were carried out on dogs to study the lung pulse by densitometry. 2. In the first group of experiments the lung was excluded from the field of densitometry by the induction of a pneumothorax and the lung pulse disappears when the lung is excluded and reappears when the lung returns into the field of observation. 3. In the second group of experiments the pulmonary artery supplying a segment of lung was obstructed by a balloon catheter. When the blood flow to the lung is occluded by the balloon the lung pulse disappears, when the blood flow returns the lung pulse also returns. 4. When perfusion of a lung is increased by obstructing the flow to the opposite lung the lung pulse is increased and reverts to normal when normal perfusion is restored.