Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Mild interstitial pulmonary edema has substantially improved compared to the prior chest radiograph from ___ . Mild - to - moderate cardiomegaly is slightly decreased . There may be a small right pleural effusion , not significantly changed . There is no pneumothorax . The mediastinal contours are normal .
    OUTPUT:
    
1 . Substantially improved mild interstitial pulmonary edema . Slightly decreased mild - to - moderate cardiomegaly . 2 . Possible small right pleural effusion , not significantly changed .