Intraorbital wood foreign body mimicking air at CT.

Computed tomography (CT) revealed a 2-cm linear area of extremely low attenuation in the left orbit of a boy who had been poked in the eye with a tree branch. The appearance and attenuation of the area suggested air, so a diagnosis of orbital emphysema was initially considered. Further research indicated that wood mimics the CT attenuation and appearance of air. A wood splinter was surgically removed from the orbit.