Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left - sided AICD device is noted with single lead terminating in the region of the right ventricle , unchanged . Mild to moderate enlargement of the cardiac silhouette persists . The mediastinal and hilar contours are unchanged . Pulmonary vasculature is not engorged . Streaky opacities in the lung bases likely reflect areas of atelectasis , and no focal consolidation is present . There is no pleural effusion or pneumothorax . Mild degenerative changes are seen in the thoracic spine .
    OUTPUT:
    
Mild bibasilar atelectasis .