Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A left - sided central venous catheter is seen with its tip at the cavoatrial junction . The lungs are clear without evidence of focal opacity or interstitial abnormality . The heart size is top - normal and the hilar contours are normal . The pleural surfaces are clear without effusion or pneumothorax .
    OUTPUT:
    
No evidence of acute chest syndrome or pneumonia .