Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A large left pleural effusion appears slightly increased in size compared to the previous study . Cardiac and mediastinal contours unchanged . There is continued left basilar opacification likely reflective of compressive atelectasis . Mild pulmonary vascular congestion is present . Patchy right basilar opacity may reflect atelectasis though infection is difficult to exclude . No right - sided focal consolidation , pleural effusion or pneumothorax is detected . No acute osseous abnormality is present .
    OUTPUT:
    
Large left pleural effusion , slightly increased in size compared to the previous study with left basilar compressive atelectasis . Mild pulmonary vascular congestion . Patchy right basilar opacity may reflect atelectasis but infection is difficult to exclude .