Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The previously large left pleural effusion has significantly decreased and is now moderate in size . The right lung and left upper lung are well aerated and clear . Dense opacity continues to overlie the left lower lung representing a combination of pleural effusion and atelectasis . The mediastinal silhouette and hilar contours appear normal . The left cardiac contour remains incompletely evaluated due to overlying opacity . A left pigtail catheter terminates in the inferior hemithorax , and there is no evidence of apical pneumothorax . Surgical clips in the right chest wall may be due to prior breast sugery .
    OUTPUT:
    
New left chest tube has resulted in decrease in large pleural effusion , now moderate in size .