Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright and lateral views of the chest provided . Large left pleural effusion with likely associated atelectasis appears similar to prior , obscuring the left heart border . Hazy right basilar opacity is likely due to atelectasis . There is no pneumothorax . The cardiomediastinal silhouette is normal where seen . Imaged osseous structures are intact . No free air below the right hemidiaphragm is seen .
    OUTPUT:
    
1 . Large left pleural effusion with associated atelectasis appears similar to prior . Superimposed infection is a possibility . 2 . Hazy right basilar opacity is likely due to atelectasis based on prior CT , but superimposed infection is a possibility .