Correlation between the findings of expiratory high resolution computed tomography, respiratory function tests and tracheal index in chronic obstructive pulmonary disease

Objectives: In this study we aimed to investigate the relationship between expiratory HRCT findings, tracheal index (TI) and pulmonary function tests in patients with chronic obstructive pulmonary disease (COPD).Materials and methods: Sixty patients diagnosed with COPD in our hospital, department of pulmonary medicine, and 65 subjects complaining of cough with normal pulmonary function tests as a control group were enrolled in the study. All subjects were evaluated with HRCT. HRCT and pulmonary function tests were performed in same day and FEV1, FVC, FEV1/FVC values were recorded. Pearson Chi-Square, Independent Samples T test, and Mann Whitney U test were used for statistical evaluation.Results: Subjects’ mean age was 55.44±10.22 years. Bronchiectasis, bronchial wall thickening, emphysema, centrilobular bronchiolar thickening and air trapping were significantly higher in COPD group than control group. In patient group, TI values were lower than control group (p < 0.001). Also there was moderate negative relationship between TI and age (p = 0.00, r = -0.48).Conclusions: Expiratory HRCT findings and TI values show various degrees of relationship with pulmonary function test results in patients with COPD. Despite normal pulmonary function tests, pathological changes can be detected in expiratory HRCT scans