Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since the prior chest radiograph performed on ___ , there has been no significant interval change in right basilar pneumothorax . Severe upper lobe predominant emphysema . Bibasilar interstitial abnormalities are similar . Remainder of the lungs are otherwise clear . No pneumothorax on the left . No pleural effusion . Cardiomediastinal contours are normal .
    OUTPUT:
    
No significant interval change in right basilar pneumothorax since ___ .