The normal roentgenographic measurement of the right descending pulmonary artery in 1,085 cases.

The dilatation of pulmonary artery and increased measurement of the right descending pulmonary artery is a most reliable roentgen sign of pulmonary hypertension. Measurement of the right descending pulmonary artery on the routine posteroanterior view of chest, especially in inspiration and expiration is absolutely necessary in making the roentgenological diagnosis of pulmonary hypertension. To determine an abnormal measurement of the right descending pulmonary artery this author's normal value for the right descending pulmonary artery size is most important. The purpose of this Part II is to report the radiological diagnosis of pulmonary hypertensions from various etiologies and other abnormal hemo· dynamics in pulmonary circulation by using this author's technique of measurement of the right descending pulmonary artery on the routine posteroanterior view of the chest.