Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: As compared to prior chest examinations , there has been interval placement of a chest tube which appears to project over the known moderate - sized left hemothorax . There is no pneumothorax . The cardiomediastinal and hilar contours remain stable . There is left upper lobe atelectasis . The right hemithorax remains clear .
    OUTPUT:
    
Interval placement of a chest tube which projects over the known moderate - sized left hemothorax . No pneumothorax .