Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is top normal . The mediastinal and hilar contours are unremarkable . The pulmonary vascularity is not engorged . There is minimal streaky opacity in the left lung base . No focal consolidation , pleural effusion or pneumothorax identified . There are no acute osseous abnormalities .
    OUTPUT:
    
Minimal streaky opacity in the left lung base . This likely reflects atelectasis though developing infection can not be completely excluded .