Changes in regional and overall lung function after bronchography

This investigation compares the effects of unilateral bronchography on classical pulmonary function parameters (spirometry, CO transfer, flow-volume curve, and arterial blood gases) and radioisotopic measurements by means of 99mTc-labeled microspheres and 81mKr. The regional changes of ventilation and perfusion were quantified by a radioisotopic index, which was established for each zone of interest: explored lung and unexplored lung. The quantitative study of regional perfusion and ventilation reveals significant reduction of ventilation for lung bases, but not for lung apices. The radioisotopic measurements show a reduction of perfusion parallel to the reduction of ventilation. There is no significant correlation between traditional pulmonary function parameters and isotopic indices. Radioisotopy proved a sensitive tool for investigation of unilateral alterations.