Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Low lung volumes . There is subtle opacification at the right lung base which may represent atelectasis , however an early developing pneumonia is a consideration . Otherwise , the lungs are clear . Heart size is normal . The mediastinal and hilar contours are normal . The pulmonary vasculature is normal . No pleural effusion or pneumothorax is seen . There are no acute osseous abnormalities .
    OUTPUT:
    
Subtle opacification at the right lung base , which may represent atelectasis , however an early developing pneumonia is a consideration .