Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is a right pigtail chest tube . No pneumothorax is appreciated . The lines and tubes 's appear unchanged in position . There is decreased left sided retrocardiac atelectasis and effusion . Bullet fragments are again noted .
    OUTPUT:
    
1 . No pneumothorax . 2 . Improved aeration of the left lung base .