Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size , mediastinal , and hilar contours are normal . Lungs and pleural surfaces are clear . Persistent mild elevation of left hemidiaphragm , not appreciably changed . Post-operative changes are observed in the cervicothoracic junction .
    OUTPUT:
    
Chronic elevation of left hemidiaphragm . No acute cardiopulmonary abnormality .