Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size appears top normal . The aorta remains tortuous with diffuse atherosclerotic calcifications . Mediastinal and hilar contours are unchanged . The pulmonary vasculature is not engorged . Patchy linear opacities in the lung bases likely reflect areas of atelectasis in the setting of low lung volumes . No focal consolidation , large pleural effusion or pneumothorax is present . Mild degenerative changes are seen in the thoracic spine .
    OUTPUT:
    
Low lung volumes and bibasilar atelectasis .