Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal radiograph of the chest shows unchanged position of right chest tube with smaller right apical pneumothorax . Stable post-operative changes in the right upper lobe and right mediastinum are noted . Otherwise , there is no relevant change .
    OUTPUT:
    
Interval improvement in right apical pneumothorax with persistent small pneumothorax seen .