Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Residual left perihilar edema is mild . Low lung volumes result in bronchovascular crowding . The postoperative cardiac silhouette is grossly unchanged . Note is made of atelectasis in the bilateral bases . No pneumothorax
    OUTPUT:
    
Low lung volumes and bibasilar atelectasis . Mild left perihilar edema .