Morphologic Findings in Central Bronchi Correlated to Lung Function Data in Obstructive Airways Disease

Summary Quantitative analyses of morphologic findings are the condition of clinico-pathological correlation studies. These quantitative analyses are possible by morphometry. The present correlation study shows that morphometry may therefore contribute to understanding the pathogenesis of obstructive airways disease: decreasing bronchial lumen and increasing volume of glandular ducts are correlated to increasing airways resistances (clinical parameters: RAW, FEV 1 ). Increasing volume of bronchial muscles is correlated with resistance of airways at quiet breathing (RAW) and less with increasing residual volume (RV). Increasing volume of bronchial glands and glandular ducts is correlated with increasing resistance at forced expiration which is clinically shown by decreasing FEV 1 . These findings can be interpreted as follows. Airway resistances are mainly influenced by airway narrowing. At quiet breathing, muscle constriction is an additional cause of increasing airflow resistance due to bronchial narrowing. At forced expiration, however, mucus plugs probably limit the airflow because thickening of bronchial glands points to increased secretory activity. Until now it is not possible to understand why bronchial muscle volume correlates with residual volume.