Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The right - sided chest drain has been removed . Small residual right apical pneumothorax measuring 7 mm in the craniocaudal plane . The mediastinum is central . No left - sided pneumothorax . The cardiomediastinal shadow is normal . No airspace consolidation . No pleural effusion . Mild spondylotic changes of the thoracic spine .
    OUTPUT:
    
Small residual right apical pneumothorax .