Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . The aorta is calcified , indicating atherosclerosis . The mediastinal and hilar contours are normal . The pulmonary vasculature is normal . The lungs are hyperexpanded and there is flattening of the diaphragms , best seen on the lateral radiograph . Increased opacity projecting over the posterior lung bases on the lateral view , potentially atelectasis or chronic interstitial markings . Infection would be difficult to exclude . Lungs are clear . No pleural effusion or pneumothorax is seen . There are no acute osseous abnormalities . Multilevel degenerative change of the visualized spine .
    OUTPUT:
    
Subtle increased opacity projecting over the posterior lung bases on the lateral view , potentially atelectasis or chronic interstitial markings . Infection would be difficult to exclude .