A study of radiographic determination of the total lung capacity in the normal Korean pre-school children

Determination of the total lung capacity (TLC) has been widely used in the evaluation of the pulmonary function. A roentgenographic method for the determination of total lung capacity of pre-school children has been studied. This method requires posteroanterior and lateral views of the chest and consists principally of the summation of a series of elliptical cylindroids into which the lungs are divided. The measurements and calculations of the total lung capacity by radiographic method were carried out in 96 cases of normal Korean pre-school children, 51 males and 45 females. The results were obtained as follows; 1. As a whole the calculation value of TLC in male was larger than that in female in the same age group in height and weight. The mean value of TLC in female was 68.4% of that in male. 2. The standard deviation of height and body weight are ± 337 ml in male and ±284 ml in female. 3. The TLC tended to show a gradual increase as height increased. A linear relationship found between the variables of height and TLC was 0.74 in terms of coefficient of correlation. The confidence interval for the coefficient of correlation was from +0.65 to +0.84 at 95 percent confidence level. 4. There was no significant correlation between the value of TLC and the body weight