Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is mildly enlarged . The mediastinal and hilar contours are unremarkable . The pulmonary vascularity is normal . There is a faint opacity within the left lung base which is most likely reflective of atelectasis . No focal consolidation , pleural effusion or pneumothorax is visualized . There is no acute osseous abnormality .
    OUTPUT:
    
Probable mild atelectasis in left lung base . No focal consolidation to suggest pneumonia . No evidence of pneumothorax or congestive heart failure .