Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes remain low . There are persistent areas of patchy opacity at the right lung base . There is mild central vascular congestion . Cardiomediastinal silhouette is unchanged and mildly enlarged . No pneumothorax is present .
    OUTPUT:
    
Low lung volumes with patchy opacity at the right lung base which likely represents atelectasis , although superimposed infection can not be excluded . Mild vascular congestion .