This was a chance finding recently on a scan of an 11 year old girl. Are there any guesses what she may have inserted up her nose?!
Easier to say what it is not - non metallic and not regular in shape. It seems well wedged in there with soft tissue surrounding it and would require a general anaesthetic to remove it. The foreign object is often associated with nasal polyps. There is a small possibility that it could be dislodged and inhaled, soits removal is probably the safest option. Coins are the most common items to get stuck in the esophagus of children. Wikipedia has an interesting endoscopic image of a toothbrush in the stomach.