Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Although there is apparent mild opacity left lung base , on the chest CT performed approximately the same time , there is no infiltrate to explain this , therefore this likely represents a summation of shadows . The cardio-mediastinal silhouette is unremarkable . No significant pleural effusion or pneumothorax .
    OUTPUT:
    
When correlated with the chest CT performed about the same time , no focal infiltrate seen .