Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes remain low . A pigtail drain projects over the left lower hemithorax . No appreciable substantial effusion on this frontal view . Bilateral left greater than right atelectasis . The heart his mildly enlarged , perhaps slightly more compared to the prior exam . Pulmonary vascular congestion is unchanged . No pneumothorax .
    OUTPUT:
    
Bilateral atelectasis and low lung volumes . No appreciable effusions on the frontal view , but conventional PA and lateral radiographs would be optimal evaluate for small effusion if desired .