We report two patients with bullous lung disease and suspected pneumothorax on plain chest radiographs. Chest tubes were inserted in both patients, but no clinical or radiological improvement occurred. Computed tomographic (CT) scans were then performed and showed bullous lesions without any pneumothorax. This permitted the removal of unnecessary chest tubes. In selected patients with severe bullous disease, CT may be useful, either on admission or later, when the diagnosis of pneumothorax by conventional radiographs is doubtful.