Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared with ___ , there has been partial clearing of the previously seen opacity at the right lung base . Patchy opacity at the left lung base is similar to the prior study . Small right - greater - than - left pleural effusions are essentially unchanged . Background hyperinflation / COPD again noted . The cardiomediastinal silhouette is similar . It appears slightly shifted to the left , unchanged . Biapical pleural thickening , right - greater - than - left , again noted . Dual lumen right - sided catheter again seen overlying the upper right atrium , similar to prior . No CHF , pneumothorax , or new focal opacity identified .
    OUTPUT:
    
Interval improvement in right base opacity , though a small amount of residual opacity remains visible at the right base . Persistent left base opacity is similar . Small right - greater - than - left effusions again noted , also similar to prior .