Figure 1
Figures 1-2. Axial and coronal CT slices through the orbits SHOW a linear hypodense area extending through the right superior orbital fissure.

Figure 2

Figure 3
Quantitative CT. The three circles depict the relative densities (Hounsfield units) of the circumscribed areas. This showed the area in question (area 2) was denser than air (area 3, within the ethmoid sinus) and less dense than orbital tissue (area 1, extraocular muscle). This helped identify the hypodense area as an intraorbital foreign body and not air.

Figure 4
Figures 4-5. Axial MRI sections confirm the area in question to be consistent with a retained intraorbital foreign body instead of tracking emphysema.

Figure 5