Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Mild enlargement of cardiac silhouette is unchanged compared to the prior study . Aortic knob is calcified . The mediastinal and hilar contours are within normal limits . No pulmonary edema is present . The lungs are hyperinflated compatible with history of COPD . Small bilateral pleural effusions are noted , with minimal streaky opacities in the lung bases compatible with atelectasis . No pneumothorax is present . No acute osseous abnormalities identified .
    OUTPUT:
    
Small bilateral pleural effusions with mild bibasilar atelectasis . COPD .