Ocular Injuries, Triage, and Management in Maxillofacial Trauma

Key points

  • Key historical information for the triage of ocular trauma includes the mechanism and nature of the injury, the presence of eyewear at the time of the injury, and the status of vision before injury.

  • Examination findings indicative of a ruptured eye are poor vision (hand motions or less); extensive subconjunctival hemorrhage; poor ocular motility in all directions; a large hyphema; or intraocular contents visible through a wound.

  • Visual acuity is the most important prognostic indicator after eye trauma and needs to be measured and recorded in a reliable way.

  • Findings of a ruptured eye require immediate consultation with an ophthalmologist.

Introduction

The most important thing one can do for a patient with facial trauma is correctly identify a concurrent severe eye injury for appropriate and timely referral to an ophthalmologist. This article provides practical information allowing one to make intelligent decisions with regard to ocular injuries in the setting of simple or complex facial injuries. Some eye injuries may not require emergency care by an ophthalmologist but can be managed initially without urgent consultation. Other injuries need urgent referral for evaluation and treatment. The goal of the surgeon or provider is to appropriately discriminate between the two. Accumulating the appropriate information and accurately presenting that information to the ophthalmologist triggers an appropriate response.

Introduction

The most important thing one can do for a patient with facial trauma is correctly identify a concurrent severe eye injury for appropriate and timely referral to an ophthalmologist. This article provides practical information allowing one to make intelligent decisions with regard to ocular injuries in the setting of simple or complex facial injuries. Some eye injuries may not require emergency care by an ophthalmologist but can be managed initially without urgent consultation. Other injuries need urgent referral for evaluation and treatment. The goal of the surgeon or provider is to appropriately discriminate between the two. Accumulating the appropriate information and accurately presenting that information to the ophthalmologist triggers an appropriate response.

History and physical examination of the patient with the traumatized eye

An accurate history of how the injury occurred is the first important piece of information to gather Box 1 . The nature of the injury can raise the suspicion of a more severe injury. Mechanisms involving high-velocity small projectiles are more concerning for penetrating ocular injuries. Typical histories in these cases involve breaking glass from bottles used as weapons, explosions of any kind, or metal-on-metal contact during industrial or tool use. Blunt-force injuries also can cause serious ocular trauma. Beatings with an object or edge small enough to fit into the opening between the orbital rims are more likely to cause direct ocular trauma. Explosive force in the absence of projectiles can rupture sclera or damage intraocular structures; a determination of the distance from an explosion and a general assessment of its power are important in building the case for a severely injured eye.

Box 1

  • Mechanism and nature of the injury

  • Eyewear at the time of the injury

  • Status of vision before injury

Critical historical information

Another useful historical detail is whether or not eyeglasses were worn at the time of the injury. A completely intact set of eyeglasses surviving trauma suggests the area of the orbit has been spared, and the eye spared with it. Conversely, a completely destroyed pair of eyeglasses with shattered or damaged lenses suggests enough destructive force to cause severe injury to the eye and surrounding tissue. The use of contact lenses at the time of the injury, the nature of those lenses (hard or soft), and the status of them after the injury are useful bits of information when evaluating the patient and discussing the case with an ophthalmologist. Historical confirmation that an eye could see and read before trauma is a critical piece of information. An eye that did not see before an injury does not see after the event.

Visual acuity

Measuring how well an injured eye can see is the first and most important step to determine the urgency of an ophthalmic evaluation. A well-determined visual acuity is a critical branch point in the decision path of ocular triage and the most important prognostic indicator in eye trauma. Poor vision equals damage to the anatomic structure of the eye or at a minimum introduction of opacities in the otherwise optically transparent ocular structures. Either way, this is when the ophthalmologist needs to sort out the problem Box 2 .

Box 2

  • Visual acuity

  • Lids

  • Conjunctiva

  • Cornea

  • Iris and pupil

Important ocular physical examination elements

An everyday visual acuity measurement is usually recorded in an eye professional’s office using a standard Snellen acuity chart. Acuity measurements using a standard chart are recorded from 20/400 to 20/20. The numerator of these fractions refers to the normal test distance of 20 ft. The denominator refers to the line on the chart that a “normal” patient should be able to see at 20 ft. In patients who are unable to see the eye chart adequately enough to read it, other approximations are recorded, such as “counts fingers at 5 feet,” “hand motion at 3 feet,” or “light perception.”

To a professional who does not routinely record visual acuity, the standard methods are likely not available. However, other methods are equally important and need to be pursued. Newspapers, magazines, and sweetener packets can be used as an estimation of acuity. The goal is to determine the best acuity possible in a potentially severely injured eye. This can be done with eyeglasses at reading distance, 14 in, or at 10 ft; however, if vision is actually better without eyeglasses it should be recorded without. However the vision is measured, the method needs to be recorded with it. Examples of appropriately recorded acuity measurements include the following:

  • “Patient is able to read with right and left eye small print on Splenda packet at about 14 in with reading eyeglasses.”

  • “Patient can read Washington Post story print at 14 in without any eyeglasses.”

  • “Patient can only accurately count fingers placed 2 ft in front of left eye with or without eyeglasses.”

  • “Patient can only perceive light or dark with the right eye using otoscope light at 6 in.”

A magnified view

If one is not an eye care professional one will not have the “right” equipment to examination an eye. A slit lamp is a biomicroscope, magnification with a light source. A maxillofacial surgeon is likely to have a pair of surgical loupes to assist in examination. Magnification is the first assistance in examining the eye. Use what is available to get a magnified view; a handheld magnifying lens is better than nothing. A pair of magnifying surgical loupes is better. Light is needed to see. Get a good source of light on the eye; brighter is better. Light the eye from the front, then the side. Different angles provide different information. Are the eyelids in the way? They need to be moved. One drop of sterile ophthalmic anesthetic to permit an examination can transform a most uncooperative patient into the most cooperative one. Retracting the lids should be done carefully. Only apply pressure on the orbital rim to retract lid tissue. Lid retractors can also be used carefully but risk the opportunity to apply pressure to the eye itself. This is usually best left for the ophthalmologist. Examining the eye, even for purposes of triage, is a skill. Practice makes perfect or at least improvement.

Clinical examination indicators of a severely injured eye

One does not have to be an ophthalmologist to recognize the pertinent examination findings of an eye that requires the attention of an ophthalmologist. However, there is a need to recognize the following key findings that distinguish a routine consultation from an emergent or urgent one.

Poor vision after facial trauma with a history suspicious for an ocular injury is probably enough to warrant an emergent evaluation by an ophthalmologist. What does “poor vision” mean? This is why an accurate measurement of acuity in the context of an accurate history is critical. An injured pilot, who by definition should have excellent vision in each eye, with loss of vision to 20/400 in one eye is an emergency. A patient with 20/80 vision who wore a patch for a lazy eye on the same side as a facial injury is not necessarily an urgent evaluation. Consultation with the ophthalmologist helps sort out the urgency of an evaluation in cases, but having the right data collected makes that discussion easier.

Subconjunctival hemorrhage is a common occurrence spontaneously outside of a traumatic event. These asymptomatic thin or small spontaneous hemorrhages are themselves harmless. A worrisome subconjunctival hemorrhage in the setting of trauma is extensive, often surrounding the cornea for 360 degrees. The hemorrhage is large, heaping up the conjunctiva enough that in some cases the lids do not close completely or are elevated off the surface of the cornea. A hemorrhage this large implies a rupture of the globe itself. The bleeding originates from the choroid beneath the sclera; in addition, liquid intraocular contents may be accumulating in the same space as the hemorrhage. A small subconjunctival hemorrhage is less worrisome in the setting of trauma unless the history is suspicious for a projectile injury and a penetrating foreign body Box 3 .

Box 3

  • Very poor vision (hand motions or less)

  • 360 degrees of subconjunctival hemorrhage

  • Poor ocular motility in all directions

  • Large hyphema

  • Visible intraocular contents through a wound

Examination findings suspicious of a ruptured globe

Poor motility in all directions of gaze is another very worrisome finding in facial trauma. Inability to infraduct or supraduct an eye may indicate a trapped and injured inferior rectus muscle. Lateral and media movement are preserved. However, poor motility in all directions is an indication of a collapsed eye. The extraocular muscles have a poor mechanical advantage on a soft and misshapen globe. It is unlikely that such an injury would occur without a large subconjunctival hemorrhage, but if noted on examination it should be discussed with the ophthalmologist.

Gross anatomic derangement of important ocular structures is a clear indication for an emergent evaluation by an ophthalmologist. Visible corneal wounds, intraocular contents prolapsing through a wound, missing sectors of iris, loss of corneal clarity, and lens material or blood layered in the anterior chamber are all conditions warranting emergency evaluation. Although surgeons may be comfortable with the repair of full-thickness lacerations, lid lacerations involving the puncta of either the upper or lower lid warrant consultation with an ophthalmologist or oculoplastic subspecialist.

Other indications of severe ocular trauma are important, but from a practical standpoint require examination skills or equipment not likely to be at the disposal of the maxillofacial surgeon. An afferent pupillary defect is a reliable indicator of damage to the eye or optic nerve. Reliable detection of this pupillary abnormality is unlikely unless specially trained and practiced in the examination for it. Vitreous hemorrhage is also a reliable indicator of severe injury, but without experience in examining intraocular structures or skilled use of special examination equipment accurate detection is unlikely. Indirect detection of vitreous hemorrhage by assessment or visual acuity is a better screening tool for the maxillofacial surgeon.

Radiographic imaging

The maxillofacial surgeon is well acquainted with the value facial computed tomography (CT) has in the management of facial trauma. In addition to the bone abnormalities seen in trauma there are characteristic findings that point to severe intraocular involvement. Attending to the soft tissues in the orbit can provide information to support a suspected diagnosis or raise the suspicion of an ocular injury requiring closer scrutiny.

Intraocular air on CT is conclusive evidence that the integrity of the eye wall has been violated. Usually a violation violent enough to trap air in the eye does not escape detection by clinical examination. Regardless of other findings on examination the presence of intraocular air on CT warrants immediate referral to an ophthalmologist. Air trapped under the lid can occur in the absence of trauma and needs to be correctly identified as such to avoid confusion.

An intraocular foreign body is conclusive finding on CT that the eye wall has been violated ( Figs. 1 and 2 ). CT protocols with thick overlapping sections are unlikely to miss a foreign body. Metal, metal containing glass, or mineral objects appear relatively radiodense and are easy to detect. Fresh vegetable matter and plain glass or sand may appear close to the density of water. Dry wood has the radiodensity of air. A large foreign body likely causes a rupture with clinical findings of poor vision and large subconjunctival hemorrhage. However, a very small sharp foreign body can penetrate the eye cleanly with minimal damage and bleeding; vision immediately afterward can be excellent. A history with the potential for small high-velocity projectiles makes this more likely. Regardless of other findings on examination the presence of an intraocular foreign body on CT warrants immediate referral to an ophthalmologist.

Jan 23, 2017 | Posted by in Oral and Maxillofacial Surgery | Comments Off on Ocular Injuries, Triage, and Management in Maxillofacial Trauma
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