Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac , mediastinal and hilar contours appear unchanged . The heart appears mildly enlarged . There is slight unfolding of the thoracic aorta . The lungs appear clear . There are no pleural effusions or pneumothorax . Mild relative elevation of the right hemidiaphragm is similar . Although this study does not include a dedicated rib series , no fracture is identified .
    OUTPUT:
    
No definite evidence of injury .