Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . Heart size is mildly enlarged . The mediastinal and hilar contours are unremarkable . There is crowding of the bronchovascular structures but no overt pulmonary edema is present . Retrocardiac streaky opacity could reflect atelectasis . No focal consolidation , pleural effusion or pneumothorax is noted . There are multilevel degenerative changes in the thoracic spine with anterior osteophyte formation .
    OUTPUT:
    
Low lung volumes with streaky retrocardiac opacity , possibly reflecting atelectasis . Infection can not be completely excluded .