Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The tip of the nasogastric tube ends in the upper esophagus , approximately 18 cm from the GE junction . The dense retrocardiac opacity appears unchanged . The heart remains enlarged . There is no pneumothorax . The PICC line is in grossly unchanged position , with the tip at least at the level of the cavoatrial junction .
    OUTPUT:
    
Nasogastric tube ends in the upper esophagus , approximately 18 cm from the GE junction . This should be advanced prior to use .