Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Moderate enlargement of the cardiac silhouette is unchanged . The mediastinal and hilar contours appear similar . The pulmonary vasculature is not engorged . Linear opacities in the lung bases are compatible with areas of subsegmental atelectasis , without focal consolidation . No pleural effusion or pneumothorax is seen . Mild degenerative changes are noted in the thoracic spine .
    OUTPUT:
    
Bibasilar subsegmental atelectasis . Otherwise , no acute cardiopulmonary abnormality .