Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . The mediastinal and hilar contours are unremarkable . Minimal opacity is noted in the left lower lobe . Remainder of lungs are clear . No pleural effusion or pneumothorax is seen . There are no acute osseous abnormalities . Remote right sixth rib fracture is again noted .
    OUTPUT:
    
Minimal opacity in left lower lobe likely reflecting atelectasis though early infection can not be completely excluded .