Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volume is low . Small left lung base opacity is probably atelectasis . Pulmonary edema is mild . Previously seen right upper lobe atelectasis is resolved . There is no pneumothorax or large pleural effusion . Cardiomediastinal silhouette is unchanged .
    OUTPUT:
    
No pneumothorax . Mild pulmonary edema . Right upper lobe now clear .