The use of radioisotope techniques for the evaluation of patients with pulmonary disease.

Although it is true that pulmonary perfusion scanning is generally accepted primarily in the differential diagnosis of pulmonary embolism, the introduction of regional ventilation studies with radioactive 133Xe, the use of the computer to provide quantitative data, and the advances being made in cardiovascular nuclear medicine indicate that nuclear medicine procedures will be used more and more in the evaluation of patients with a variety of lung and heart diseases. They have already proved of value in the following circumstances: (1) differential diagnosis of pulmonary embolism; (2) assessment of regional involvement in pulmonary parenchymal disease, including degenerative, neoplastic, and infectious diseases; (3) detection of bullous disease and the determination of the possible effectiveness of surgery; (4) assessment of the response to radiation therapy in patients with carcinoma of the lung; (5) detection of pulmonary venous hypertension in patients with mitral valve or left ventricular disease; (6) detection of cor pulmonale; (7) differential diagnosis of cyanosis in newborn infants.