Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are hyper - expanded and clear aside from a small , stable region of lingular atelectasis adjoining the left heart border . The cardiomediastinal silhouette , hilar contours , and pleural surfaces are otherwise normal . No pleural effusion or pneumothorax is present . There is mild bilateral acromioclavicular osteoarthritis .
    OUTPUT:
    
No acute intrathoracic process .