Please check out our Oculoplastic and Orbital Procedures section for more information about the products mentioned in this article.
Orbital fractures are most commonly due to blunt trauma, either after a motor vehicle accident, sporting event or altercation. The force of the blunt object puts enough pressure on the orbital contents that the bony walls of the orbit take the brunt of the hit, breaking to create room in the orbit so that the globe does not suffer the blow. In some instances, breaks in the bone are not enough and the globe ruptures as well. This article will discuss the work up and management of an orbital wall fracture.
Upon initial presentation, the patient must be evaluated systemically to ensure stability of the airway, breathing and circulation. After stabilization, the eye and orbit is inspected. First, a ruptured globe must carefully be ruled out. If an orbital fracture is repaired in the face of a ruptured globe, the resulting decrease of orbital volume plus manipulation during the procedure will put the globe at risk for further extrusion of intraocular contents. If the patient has nausea and vomiting, suspicion should arise for an entrapped extraocular muscle, making repair an urgent matter.
Evaluation of the orbit:
A thorough history should be taken, including mechanism and time of injury. If a loose foreign body was involved this needs to be taken into consideration when choosing scans, deciding on antibiotic treatment and exploration of the orbit. The patient should be asked about the presence of diplopia or cheek hypoesthesia.
Elements of a routine eye exam must be performed, including visual acuity, slit lamp examination, intraocular pressure and dilated fundoscopic exam. Ocular motility must be checked as well as sensation in the distribution of the infraorbital nerve. The pupils must be checked. If an afferent papillary defect is present, consider that either a piece of bone is impinging on the nerve or a retrobulbar hematoma or foreign body is abutting the nerve. An external examination is performed with special attention to enophthalmos as the increased volume in the orbit allows the globe to fall posteriorly.
Measurements can be made with a Hertel exophthalmometer.
As an alternative, the Mourits Parallax-free exophthalmometer or the Luedde exophthalmometer
can be used. In the case of trauma to the lateral orbital wall, the Naugle exophthalmometer is helpful as it rests on the superior and inferior orbital rims as opposed to the lateral rim.
Indications for the treatment of an orbital fracture include: diplopia, enophthalmos greater than 2mm and a large fracture involving >50% of the orbital wall.
To evaluate the extent of the fracture, the best imaging modality is a CT scan without contrast of the orbits with thin cuts in axial and coronal orientations. The bony windows will outline the walls nicely and fractures are easily visualized. An MRI in this situation is much less helpful and can be dangerous if the injury involved a metallic foreign body. The most common wall to be fractured is the orbital floor, followed by the medial wall.
Once the fracture is identified and surgical intervention is deemed appropriate, surgery is planned. The patient needs a thorough medical screening. Ideally the patient should be off of blood thinners for at least 2 weeks. Patients should be made aware of the potential risks involved in the surgery, including bleeding, infection, diplopia, cheek numbness, loss or decrease of vision, ptosis, and pupil abnormalities. Timing of orbital fracture repair is controversial. Many prefer to wait 2 weeks in order to let swelling subside, but waiting much longer poses a risk as fibrosis will make repair more difficult. In the situation where there is nausea, vomiting or other systemic problems involved, repair should be undertaken earlier. Otherwise, if repair is postponed, the patient should be placed on antibiotics since the sinus is in direct communication with the orbit. A nasal decongestant should be used and the patient should refrain from nose blowing in order to decrease the risk of an air embolus that can cause blindness from optic nerve compression.
The surgery is best done under general anesthesia. Once the fracture is identified intraoperatively and all prolapsed tissue is returned to it’s appropriate place, an implant can be used to cover the defect. Options are porous polyethelene, such as the sheets made by Porex Surgical.
They come in a variety of sizes and thicknesses. Some have a smooth surface to be placed on the orbital side to encourage improved motility. Some sheets have channels for suturing. There are also Supramid sheets made of nylon foil that are completely smooth on both sides. These also come in a variety of sizes.
For larger fractures involving the rim, titanium can be helpful, such as those made by Synthes.
These come in all different shapes, sizes and thicknesses. They can be cut to fit the dimensions required and are secured into place with specially made screws that come in the set. Both Synthes and Porex also make porous polyethelene coated titanium plates. These are nice because they provide the support needed for large fractures and are covered by a smooth porous surface to prevent the orbital tissues from scarring down to the titanium plate.
All of the above mentioned implants are very easy to work with and can all be cut to the size and shape needed for each individual fracture.
After the implant is placed, forced ductions are performed to ensure that the extraocular muscles are not entrapped. The wound can then be closed. After the surgery it is wise to place the lower eyelid on stretch with a Frost suture to prevent retraction if the floor was repaired. Patients are usually observed overnight for bleeding and pain.
Most patients do very well after an orbital fracture repair. Some have diplopia for several weeks as inflammation of the muscle subsides. Some may also have persistent cheek numbness.It is important to make the patients aware of this post-operative finding. It is also important to inform patients to take extra precautions because now that the orbital wall is reinforced, it will no longer take the brunt of the trauma in a repeat situation. Instead, force will be directed to the globe. There should rarely be the need for a repeat operation, as long as the orbital contents are returned to the orbit and the defect is adequately covered with a proper sized implant.