Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Bilateral pigtail catheters are present on the right and the left side . A left apical pneumothorax is thought to be present . This is not evident on the prior chest x-ray . Atelectasis at both bases is present , somewhat more marked than previously . Blunting of both costophrenic angles is again noted .
    OUTPUT:
    
Left apical pneumothorax not present on prior film .