CC
A 36-year-old male is seen in the emergency department after an assault. He explains that he was “jumped, robbed, beaten, and punched in the left eye.” You are asked to evaluate the patient for maxillofacial injuries.
HPI
The patient was returning from work when he was assaulted. He received a right-handed blow with a fist to the left upper face (a common pattern of injury). He reports no loss of consciousness but has difficulty seeing out of his left eye, and his cheek is numb (hypoesthesia of the V2 cutaneous distribution is suggestive of an orbital floor, zygomaticomaxillary complex [ZMC], or isolated anterior maxillary wall fracture).
PMHX/PDHX/medications/allergies/SH/FH
Noncontributory. The patient has no previous history of maxillofacial trauma.
Patients with a previous history of orbital floor reconstruction are at a higher risk of globe rupture with subsequent trauma to the globe because the reconstructed orbital floor is less likely to fracture. The energy delivered to the eye is absorbed by the globe (as opposed to being dispersed by fracture of the floor), causing more devastating injuries (blindness).
Examination
The initial evaluation of a trauma patient should follow the Advanced Trauma Life Support protocol.
Primary survey
The patient’s primary survey is intact; he has a Glasgow Coma Scale score of 15.
Secondary survey
General. The patient is a well-developed and well-nourished male in no acute distress.
Vital signs. Blood pressure is 135/84 mm Hg, heart rate is 108 bpm (tachycardia), respirations are 16 breaths per minute, and temperature is 37.6°C.
Maxillofacial. There is moderate left midface edema with left V2 hypoesthesia. There is no loss of malar projection (seen with displaced ZMC fractures). The intercanthal distance is maintained at 32 mm with a negative bowstring test result. (A positive bowstring test result is seen with naso-orbito-ethmoid [NOE] fractures.)
Eyes. Examination of the left eye reveals subconjunctival hemorrhage (ruptured blood vessel that leaks into the space between the conjunctiva and sclera), chemosis (inflammation and edema of the conjunctiva), and mild periorbital edema ( Fig. 58.1 ).
Vision, pupil, and pressure are the “vital signs” of the eye. After a thorough medical history and adnexal examination, it is important to check these measurements before dilating the eye. (Vital signs may change with dilation.) The vision assessment that is most important is the “best corrected vision.”
The current patient’s visual acuity was 20/20 in the right eye and 20/40 in the left eye, determined using a 14-inch near card. The pupils were equal, round, and reactive to light (5 mm to 3 mm) with accommodation. Assessment of direct and consensual visual reflexes revealed no abnormalities. (The “swinging flashlight test” is based on the consensual light reflex and is the best method for diagnosing a relative afferent pupillary defect [RAPD], also called a Marcus-Gunn pupil. Illumination of one eye that results in failure to constrict in the pupils of both eyes suggests an RAPD of the illuminated eye or a defect of the afferent visual pathway of the illuminated eye.)
A tonometer pen revealed a globe tension pressure of 12 mm Hg. (Tonometry measures the intraocular pressure [IOP], which, when high, may raise suspicion for a retrobulbar hemorrhage. An extremely low value is suggestive of globe rupture. Normal IOP ranges from 11 to 20 mm Hg. Gentle digital palpation of the closed upper eyelid is a crude assessment of IOP; although slight increases in IOP cannot be detected, a rock-hard eye should raise concern about a marked increase in IOP.)
An additional useful test is the red color saturation test, which is the most sensitive and best measure of optic nerve function. The two eyes are evaluated separately. A red object is held in front of the patient, who is asked whether the object seems to have the same color (hue) and brightness (intensity) in each eye. If the optic nerve has been damaged (e.g., by optic neuritis or increased IOP), the red object appears duller and more brown or grayish to the affected eye compared with the contralateral eye.
In the current patient, evaluation of the extraocular muscles of the left eye revealed restriction of upward gaze (suggestive of inferior rectus entrapment). There was no evidence of monocular diplopia within 30 degrees of primary gaze. (Monocular diplopia should be investigated for retinal detachment or lens dislocation.) The patient reported binocular diplopia within 20 degrees of primary gaze. (This is commonly seen secondary to edema, neuromuscular paralysis, or extraocular muscle entrapment. To determine what muscle groups and nerves are involved, the clinician should determine what gaze directions improve and worsen the doubling.)
After administration of a topical mydriatic agent and fluorescein dye to the eye, a slit-lamp examination was performed with a cobalt blue light in an anterior-to-posterior sequence. This revealed no abnormalities of the bilateral adnexa (eyelids and lacrimal system) and no corneal abrasions, opacities, or foreign bodies. There was no evidence of blood within the anterior chamber (hyphema) and no evidence of injury to the iris (traumatic iridialysis) or lens (dislocation or subluxation). (Traumatic iridodialysis occurs when the iris is torn from its root. A red reflex can be seen through the tear. Surgical repair is indicated only if decreased visual acuity or diplopia persists. The use of mydriatic agents to dilate the pupil of the eye is relatively contraindicated in patients who have sustained head injuries because of the need for multiple-interval neurologic examinations.)
Fundoscopic examination of the posterior segment (vitreous, retina, and optic nerve) revealed no vitreous or retinal hemorrhage. There were no apparent tears or foreign bodies. A forced duction test was performed after administration of a topical anesthetic and revealed true incarceration of infraorbital contents. (For this test, one or two fine forceps are used to carefully move the eye in the directions of gaze while feeling for mechanical restriction. Further measurements of globe position include those based on the surrounding bone [e.g., Hertel exophthalmometer using the zygomaticofrontal region or Naugel exophthalmometer using the frontal bone]. If these bony landmarks are displaced or significant soft tissue edema is present, reliable readings are difficult to obtain.)
The remainder of the current patient’s maxillofacial examination revealed hypoesthesia of the left V2 distribution. No palpable bony step deformities of the left orbital rim were noted.
Imaging
Computed tomography (CT) is the gold standard for assessing the status of the bony orbit. For the current patient, a facial helical CT scan (1-mm cuts) without contrast was obtained after the primary and secondary surveys were completed. Coronal views (best view of the internal orbit) reveal a fracture of the left orbital floor with complete opacification of the maxillary sinus ( Fig. 58.2 A). Sagittal views showed the location of the fracture in an anterior-posterior dimension ( Fig. 58.2 B). (Three-dimensional reconstruction views add little information for the preoperative planning of orbital floor fractures, except for teaching purposes.)
Labs
For the management of isolated orbital floor injuries, no routine laboratory testing is indicated unless dictated by the medical history. When evaluated as part of the treatment of a multisystem trauma patient, routine laboratory tests include a complete blood count, complete metabolic panel, liver function tests, and coagulation studies.
Assessment
Isolated fracture of the left orbital floor with entrapment of the inferior rectus muscle; Facial Injury Severity Scale score of 1.
Treatment
A much-disputed topic is which orbital floor fractures require treatment. Surgical intervention may be required in two clinical situations: globe malposition and diplopia. Several factors can be helpful in determining whether a pure blowout fracture requires internal orbital surgery; these factors can be broken down into absolute indications, relative indications, and contraindications to immediate repair.
Absolute indications
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Globe malposition with acute enophthalmos, hypoglobus, or both
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Immediate correction of diplopia in the setting of muscle (inferior rectus) incarceration and a positive forced duction test result or unresolved diplopia with a positive forced duction test result
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Immediate correction in the symptomatic pediatric patient with an orbital floor “trapdoor” fracture that has elicited a oculocardiac reflex (the oculocardiac reflex can be seen with true entrapment)
Relative indications
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Prevention of a cosmetic deformity. Disruption of greater than 50% of the orbital floor is likely to cause cosmetically apparent enophthalmos, especially with fractures in the critical area at the junction of the floor and medial wall.
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Correction of unresolved diplopia (7–11 days) in the setting of soft tissue prolapse.
Contraindications to immediate repair
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Any condition that puts the globe in jeopardy, such as ocular injuries (e.g., hyphema, retinal tears, lens displacement). For example, a lacerated globe or hyphema may put the globe at increased risk because of the retraction necessary to perform orbital surgery.
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The status of the noninjured eye as a possible contraindication. Diplopia (binocular) would not be possible in a patient with one blind eye; therefore, the only reason to perform surgery, other than restriction of globe motion secondary to incarceration of soft tissues, would be to prevent globe malposition.
The current patient had binocular diplopia within 20 degrees of primary gaze, a positive forced duction test result with concurrent evidence of greater than 50% orbital floor disruption, and a high likelihood of cosmetically significant postinjury enophthalmos.
The patient was taken to the operating room 4 days after the assault to allow for partial resolution of soft tissue edema. A preseptal (between the septum and the overlying orbicularis oculi muscle) transconjunctival incision was made, without the need for a lateral canthotomy ( Fig. 58.3 A). After the bony defect was isolated ( Fig. 58.3 B), a preformed orbital floor plate was fitted and then properly further contoured and fixated ( Fig. 58.3 C and D). A forced duction test, which was confirmed with the contralateral side, showed full mobility of the eye in all directions. The incision was closed with 5-0 fast-absorbing gut suture, and a frost suture was placed. A postoperative CT scan ( Fig. 58.4 ) revealed proper positioning and contour of the reconstruction plate.
