Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are low lung volumes . There is a diffuse interstitial process which is predominantly scarring , as evidenced by a chest CT from ___ . Superimposed on chronic interstitial scarring is mild edema , but no large pleural effusion . Heart size is mildly enlarged , but stable . No pneumothorax .
    OUTPUT:
    
Chronic interstitial changes with superimposed edema . No large pleural effusion .