Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . The mediastinal and hilar contours are within normal limits . The pulmonary vasculature is not engorged . Linear opacities in both lung bases are compatible with areas of subsegmental atelectasis . No focal consolidation , pleural effusion or pneumothorax is demonstrated . Minimal degenerative changes are noted in the thoracic spine .
    OUTPUT:
    
Bibasilar subsegmental atelectasis . No focal consolidation to indicate pneumonia .