Pulmonary technetium-99m diethylene triamine penta-acetic acid aerosol clearance as an index of lung injury.

Although the clearance of an inhaled nebulised radioaerosol has long been employed as a measure of lung function, this test has not found favour in nuclear medicine units to the extent that might originally have been anticipated. In this review the theoretical basis of solute transfer is considered and the measurement of radioaerosol clearance discussed. Thereafter the various clinical applications of alveolar permeability measurement are outlined. Finally, possible reasons for the restricted clinical use of the diethylene triamine penta-acetic acid clearance technique are considered. It is concluded that the technique should provide a rapid screening evaluation of the HIV+ve patient presenting predominantly with chest symptoms.