Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is a subtle opacity in the left lower lobe which appears to be new compared to the prior radiograph in ___ . This could represent atelectasis , but pneumonia should be considered in the appropriate clinical setting . No pleural effusions or pneumothorax . Cardiomediastinal silhouette is within normal limits . No acute osseous abnormalities identified .
    OUTPUT:
    
Subtle left lower lobe opacity that is new from ___ , and could represent pneumonia in the appropriate clinical setting .