Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . The aorta is tortuous ; otherwise , the hilar and mediastinal contours are normal . The lungs are clear without evidence of focal consolidations concerning for pneumonia . There is mild left apical scarring . There is no pleural effusion or pneumothorax . Old bilateral healed rib fractures are identified . Note is also made of mild emphysema .
    OUTPUT:
    
No acute intrathoracic abnormalities identified . Mild bibasilar atelectasis .