Roentgenographic Study of the Chest of the Aged: special reference to "senile lung" and the paraspinal line

The characteristics of the changes of "senile lung" and normal values of the width of the paraspinal shadows on the chest roentgenographs were studied among 235 subjects aged from 70 to 97 without frank chest diseases. The ratio of upper transverse diameter (at the level of posterior 6th rib) to lower transverse diameter (at the top of right hemidiaphragm) on the frontal radiographs was significantly higher over the age of 85 than under 84, only in the female subjects. However, a lack of differences could be found in males. Therefore, "senile lung" was considered to be characteristic of the aging process, only for women.
The width of the paraspinal shadow over the age of 70 was estimated to be normal in up to 19.9mm, and the index divided by the distance of descending aorta was up to 0.61, obtained from the value of 99% confidence limits.