Imaging of orbital trauma

Abstract

Assessing traumatic orbital injuries is an important challenge for radiologists; this assessment is even more difficult when the orbital injury is associated with injuries involving multiple organs. Common posttraumatic orbital injuries include anterior chamber injuries, injuries to the lens, open-globe injuries, ocular detachments, intraorbital foreign bodies, carotid cavernous fistula, and optic nerve injuries. Radiographic examination of the orbits is rarely performed. Ultrasonography (US) can be very useful for evaluating the globe and its contents; however, US is contraindicated if a ruptured globe is suspected. Magnetic resonance imaging may be difficult to perform emergently; it is contraindicated if there is a possibility that a metallic intraorbital foreign body is present. Computed tomography (CT) is considered to be the top choice for evaluating orbital trauma. The best protocol is to obtain thin-section axial CT scans, then to perform multiplanar reformation. When evaluating a patient with an orbital injury, the radiologist should do the following: (a) evaluate the bony orbit for fractures, note any herniations of orbital contents, and pay particular attention to the orbital apex; (b) evaluate the anterior chamber; (c) evaluate the position of the lens (the lens may be displaced, and it may be either completely or partially dislocated); (d) evaluate the posterior segment of the globe, look for bleeds or abnormal fluid collections, and evaluate for radiopaque or radiolucent foreign bodies; and (e) evaluate the ophthalmic veins and the optic nerve complex, especially the orbital apex.