Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since the prior study , there has been interval removal of a left chest tube , with development of a moderate upper left pneumothorax . There is no mediastinal shift . No pleural effusions are identified . The lungs are clear , with mild right apical thickening , likely from blebs , unchanged . The heart size is normal . Chain sutures are again noted along the upper left hilus .
    OUTPUT:
    
Moderate left pneumothorax following removal of left chest tube .