Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are well expanded . Scarring is seen in the lung apices . There is retrocardiac opacity which may represent atelectasis , but can not exclude pneumonia or aspiration in the right clinical setting . No other nodule , consolidation , or mass is seen . There is a small left pleural effusion . There is no right pleural effusion . There is no pneumothorax . The cardiomediastinal silhouette is unremarkable .
    OUTPUT:
    
1 . Retrocardiac opacity which may represent atelectasis , but can not exclude pneumonia or aspiration in the right clinical setting . 2 . Small left pleural effusion .