Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lungs are clear without confluent consolidation . A chronic moderate left pleural effusion appears similar in size compared to recent prior examination . Associated left lower lobe atelectasis is likely . There is no overt interstitial pulmonary edema . Cardiomediastinal and hilar contours are within normal limits . There is no pneumothorax .
    OUTPUT:
    
Unchanged moderate left pleural effusion with probable associated atelectasis . No acute cardiopulmonary process .