We report the main findings of inspiratory and expiratory high-resolution computed tomography (HRCT) of the thorax in three women aged between 29 and 46 years with constrictive bronchiolitis and compare these results with the anatomopathological findings. The three women presented with progressive noncharacteristic dyspnea and were submitted to pulmonary function tests, HRCT of the thorax and lung biopsy. In two of the patients, inspiratory and expiratory HRCT of the thorax demonstrated a mosaic attenuation pattern that was accentuated during expiration. The expiratory phase was not performed in the third patient who presented centrilobular nodules. The pathology studies revealed significant bronchiolar stenosis due to fibrous thickening of the lamina propria and atrophy of the bronchiolar epithelium, which are diagnostic findings of constrictive bronchiolitis. Inspiratory and expiratory HRCT demonstrated to be of fundamental importance in the assessment of patients with diseases that cause obstruction of small airways. The mosaic attenuation pattern in the expiratory phase is characteristic of the peripheral topography of the lesions. The diagnosis of constrictive bronchiolitis should be confirmed by lung biopsy.

Keywords: Thorax, Bronchiolitis, High-resolution computed tomography, Anatomopathology