Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Minimal opacity at the lung bases correspond with dependent atelectasis seen on the current CT . Otherwise , the lungs are clear . There is no focal consolidation or pneumothorax . No vascular congestion , edema or pleural effusions are evident . The thoracic aorta appears tortuous and the ascending aorta appears mildly dilated . The hilar contours are within normal limits . The heart size is normal .
    OUTPUT:
    
Mild bibasilar atelectasis . Dilated ascending aorta .