Airway changes in chronic pulmonary embolism: CT findings in 33 patients

PURPOSE: To evaluate airway changes in chronic pulmonary embolism with computed tomography (CT). MATERIALS AND METHODS: CT findings in 33 patients with chronic pulmonary embolism (group 1) were retrospectively compared with those in a control group of 19 patients with acute pulmonary embolism (group 2). Bronchial abnormalities were analyzed on thin-section CT scans; vascular signs of pulmonary embolism were evaluated on spiral CT angiograms obtained at the same session. In group 1, pulmonary function test results were available in 15 patients and serial CT scans were obtained in nine patients (mean follow-up, 17.7 months). RESULTS: In group 1, cylindric bronchial dilatation was found in 21 (64%) patients versus two (11%) patients in group 2 (P < .001) at the level of segmental and/or subsegmental bronchi and in the absence of obstructive syndrome. Bronchial wall thickening was identified in four (12%) patients in group 1 and in two (11%) patients in group 2 (P = .6). In group 1, concordance was found between the location of bronchial dilatation and that of completely obstructed and retracted pulmonary arteries (kappa = 0.70), with a lower lobe predominance for bronchial dilatation. Follow-up CT scans demonstrated no changes in airway caliber over time. CONCLUSION Chronic pulmonary embolism may lead to ipsilateral proximal bronchial dilatation.