Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . Cardiomediastinal silhouette and hilar contours are normal . Lungs are clear but low in volumes . Pleural surfaces are clear without effusion or pneumothorax .
    OUTPUT:
    
No acute cardiopulmonary abnormality , specifically no pneumothorax . Rib fractures are better defined on the same day outside hospital chest CT .