Imaging Studies
Intraoperative Imaging
Assessment of a patient with suspected orbital wall injury includes a detailed oculofacial examination as well as radiologic imaging. Surgical repair with or without an implant may be indicated for diplopia, enophthalmos, or both. [3] Intraoperative imaging is gaining widespread use in the management of facial fracture repair. Use of intraoperative imaging allows the surgeon to make real-time changes in operative management ranging from repositioning the orbital plate to deciding whether to proceed with orbital floor exploration. This not only allows for immediate optimization of repair but also could decrease the need for revision procedures, thus decreasing patient morbidity and improving patient outcomes. Long-term follow-up management for patients with orbital fracture with intraoperative computed tomography (CT) is suggested. [18, 19]
Radiographs
Computed tomography is replacing plain films in evaluation of orbital trauma because of higher sensitivity and better definition of injuries. When CT is not available, or when there is low suspicion without ocular symptoms, plain films can be used.
Obtain routine facial views, including Waters, Caldwell, and lateral projections.
Waters view best displays inferior orbital rims, nasoethmoidal bones, and maxillary sinuses. If the patient is upright when the film is taken, an air-fluid level can often be seen in the maxillary sinus, which may indicate fracture of the maxillary sinus (orbital floor).
If the patient is immobilized on a backboard when the film is taken, blood layers form in the posterior of the sinus, making it appear clouded. Another sign of orbital blow-out fracture is the teardrop sign—an opacification in the upper maxillary sinus that represents periorbital fat and possibly an entrapped extraocular muscle in the maxillary sinus.
Caldwell projection provides the best view of the lateral orbital rim and the ethmoid bone.
Lateral views are the least helpful, but if the patient is lying supine on the backboard, he or she may show air-fluid levels in the posterior of the maxillary sinus.
Cervical spine radiographs may be indicated in patients with severe facial injuries or with a consistent mechanism and/or neck pain.
Computed tomography
Depending on the institution and the severity of the incident, CT scanning is generally considered the test of choice to diagnose facial/orbital fractures. Benefits over other imaging approaches include increased sensitivity, improved ability to plan for operative repair when needed, and utility in diagnosing associated injuries. [2, 14]
Orbital blow-out fractures may require CT scanning for evaluation of the floor and medial wall of the orbit. In the emergent setting, CT scanning may not be needed if the patient has no ocular injury or entrapment. However, for patients with decreased visual acuity, this test is helpful in diagnosing direct optic nerve involvement in the fracture and the presence of retro-ocular edema or hematoma, which can stretch the optic nerve.
For severe injuries in the orbit area, facial CT scanning may identify associated orbital rim, nasoethmoidal, and zygomaticomaxillary fractures.
Consider CT scanning of the brain to exclude concomitant intracranial injuries.
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Left orbital floor fracture. This patient presented with little motility disturbance; however, because of the large defect in the orbital floor, late enophthalmos was predicted. Surgical repair was undertaken. Note the pneumo-orbitum.
