Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Retrocardiac opacification may represent early consolidation in the proper clinical setting . There is no pleural effusion , pneumothorax , or pulmonary edema . The cardiomediastinal silhouette is normal . Left sixth and seventh rib fractures appear subacute or chronic .
    OUTPUT:
    
1 . Retrocardiac opacification may represent an early consolidation in the proper clinical setting . 2 . Subacute or chronic left sixth and seventh rib fractures .