Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . Moderate enlargement of the cardiac silhouette is unchanged . The mediastinal and hilar contours are similar . Mild pulmonary edema is slightly improved compared to the prior study . A trace left pleural effusion may be present . There is no focal consolidation or pneumothorax . Mild degenerative changes are seen throughout the thoracic spine .
    OUTPUT:
    
Mild pulmonary edema , slightly improved in the interval , with possible trace left pleural effusion .