Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest . There is a vague opacity seen over the left mid lung , best appreciated on the frontal view . No pleural effusion or pneumothorax . The heart is mildly enlarged and unchanged . The mediastinal and hilar structures are unremarkable . An acute - appearing nondisplaced rib fracture is seen in the posterior left seventh rib .
    OUTPUT:
    
1 . Nondisplaced left seventh rib fracture . 2 . Vague opacity in the left mid lung may reflect contusion or aspiration . These findings were discussed with Dr . ___ by Dr . ___ at 11 p .m . on ___ by telephone .