Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Re-identified are sternotomy wires . There are low lung volumes . Allowing for this , the cardiomediastinal silhouette is unchanged . Prominent pulmonary vessels and diffuse interstitial prominence is likely a combination of crowding of normal bronchovascular structures and pulmonary venous congestion without overt edema . Retrocardiac opacity may represent atelectasis , however difficult to exclude superimposed pneumonia in the appropriate clinical setting . There is no pneumothorax or pleural effusion .
    OUTPUT:
    
1 . Retrocardiac opacity may represent atelectasis , however can not exclude superimposed infection in the appropriate clinical setting . 2 . Very low lung volumes and crowding of normal bronchovascular structures . 3 . Pulmonary venous congestion without overt edema .