Correlation between functional and morphological airways indexes in bronchiectasis subjects

Background: Bronchiectasis (BC) diagnosis is based on clinical findings, high-resolution computed tomography (HRCT), and by pulmonary function tests (PFT) as a complementary evaluation. When compared to spirometry, which is the most common used PFT, Impulse Oscilometry System (IOS) detects early changes in respiratory system both in central and peripheral airways. Objective: To correlate PFT, evaluated by spirometry and by IOS, with the area of the lumen obtained in HRCT in BC subjects. Methods: Thirty eight clinically stable non-cystic fibrosis BC subjects were evaluated by HRCT (area of the lumen measurements in the 3rd and 4th bronchial generations (AL3 and AL4)), spirometry (FVC% and FEV1%), and IOS (R5 and R20: airway resistance at 5 and 20 Hz). Results: AL3 showed significant correlation (p Conclusion: The area of the lumen analysed by the HRCT shows a higher correlation with IOS than with spirometry parameters.