Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Linear opacities within the lung bases , left greater than right , correspond with atelectasis seen on concurrent CT . No confluent opacity is identified to suggest pneumonia . There is no pulmonary edema or pleural effusions . No pneumothorax is evident . Mediastinal and hilar contours are within normal limits . Mild enlargement of the cardiac silhouette is unchanged . There is no subdiaphragmatic free air .
    OUTPUT:
    
1 . Minimal bibasilar atelectasis . 2 . Unchanged mild cardiomegaly .