The change in the distribution of Tc-99m human serum albumin radioaerosols in asthma after a 1-week course of corticosteroid inhalation treatment.

This study evaluated the effects of corticosteroid inhalation on the deposition pattern of Tc-99m HSA radioaerosols in 24 patients with asthma. The homogeneous degree of depositing radioaerosol was quantitatively evaluated using a modified standard score system over both lungs. The baseline scores were calculated before inhalation therapy of 0.05 mg beclomethasone dipropionate four times daily for 1 week. The studies were then repeated after treatment to evaluate the effects of inhalation therapy. After treatment, the scores decreased in 16 of 24 cases (67%), which means that the degree of the bronchial obstruction decreased. The statistical results revealed significant differences in the total homogeneity score (P < 0.001) before and after therapy. Thus, a 1-week course of beclomethasone dipropionate inhalation therapy improves the bronchial obstruction in asthma patients as shown by the quantitative homogeneity score system of the Tc-99m HSA radioaerosol inhalation lung scintigraphy.