Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . The heart size is top normal . Mediastinal and hilar contours are unchanged with calcification of the aortic knob re - demonstrated . The pulmonary vascularity is normal . Minimal atelectasis is seen in the retrocardiac region . No focal consolidation , pleural effusion or pneumothorax is present . There are no acute osseous abnormalities .
    OUTPUT:
    
Minimal retrocardiac atelectasis in the setting of low lung volumes . No focal consolidation to indicate pneumonia .