Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . Mediastinal and hilar contours are unremarkable . The pulmonary vasculature is normal . Linear opacities within both lung bases likely reflect areas of subsegmental atelectasis . No focal consolidation , pleural effusion or pneumothorax is present . Hyperinflation of the lungs with attenuation of the pulmonary vascular markings in the upper lobes suggests emphysema . Mild degenerative changes are noted in the thoracic spine .
    OUTPUT:
    
Mild bibasilar subsegmental atelectasis . Otherwise , no acute cardiopulmonary abnormality .