Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A predominantly upper lobe interstitial abnormality has been more severe recently , probably due to concurrent edema at the time . Moderate to severe was shown on recent Chest CT . There is no pleural abnormality or lung consolidation . The cardiomediastinal silhouette and hila are normal . A right VP shunt seen .
    OUTPUT:
    
1 . Moderate to severe centrilobular emphysema . 2 . No acute cardiothoracic process . 3 . Predominantly upper lobe interstitial disease , previously exaggerated by edema .