Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lungs are moderately well inflated . Dense left retrocardiac opacity , atelectasis versus consolidation . No pneumothorax or pleural effusion noted . Stable mild cardiomegaly . Aortic knuckle calcification persists . No significant interval change in the bony thorax .
    OUTPUT:
    
Dense left retrocardiac opacity , atelectasis versus consolidation . No pleural effusion or pneumothorax present .