Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There has been interval placement of a left thoracostomy tube , with slight decrease in size of a known left pneumothorax . Subcutaneous gas overlies the tube entry site . The right long remains clear . The heart size is normal . The hilar and mediastinal contours within remain within normal limits . Multiple left - sided rib fractures are again demonstrated .
    OUTPUT:
    
Interval slight decrease in size of a left pneumothorax following placement of a left thoracostomy tube .