1. MAINTAIN HIGH SUSPICION OF OCULAR INJURIES

The mechanism of injury will often suggest an ocular injury. Direct trauma with ocular laceration may be fairly obvious, but blunt trauma leading to an occult rupture on the posterior aspect of the globe or injury to the retina can be easily overlooked in a multitrauma patient. Small metallic fragments can penetrate the eye and leave it appearing deceptively intact. An awake and alert patient can report change in vision or eye pain; an unconscious patient cannot. Thermal burns to the face frequently cause eyelid burns and contraction, which increase the risk for exposure keratopathy. Critical details in the evaluation of ocular trauma include mechanism of injury and presence of properly worn ballistic eyewear at the time of injury.

2. ASSESS AND DOCUMENT VISUAL FUNCTION

Visual acuity is the vital sign of the eye. Whenever possible, visual acuity should be assessed and documented. Visual function immediately after trauma is an important prognostic indicator for visual outcome. Visual acuity can be effectively estimated with several field-expedient methods, starting with ability to read any printed letters such as labels on medical supplies. If the patient is unable to read letters, assess their ability to count fingers. If they cannot count fingers, evaluate for the ability to detect hand motions. If they cannot detect hand motion, evaluate light perception using a bright light. Document visual acuity along with other vital signs.

Assessing for a relative afferent pupillary defect (RAPD, also called the swinging flashlight test or Marcus Gunn Pupil; Appendix A) gives an indication of retina and optic nerve function. Shine a light in either eye; normally, both pupils should constrict equally. This reaction to light is equal unless there is damage to the optic nerve or the retina, in which case the pupil of the injured eye will dilate when the light is shone in the injured eye. Evaluating for an RAPD is essential in conditions such as retrobulbar hemorrhage (orbital compartment syndrome) or suspected retinal detachment. Notation of an RAPD is also an important prognostic factor for ophthalmic providers at later level of care.

3. EXAMINE FOR CRITICAL PHYSICAL FINDINGS

An obvious globe laceration or rupture with prolapsed intraocular contents can be a striking picture but may not be present in every severe eye injury. At times, the only findings of a significant eye injury may be penetrating periocular trauma or lid lacerations, a peaked or teardrop pupil, or abnormal anterior chamber depth.

Estimation of intraocular pressure (IOP) is essential in injuries such as retrobulbar hemorrhage, but is contraindicated in injuries with obvious or suspected open globe injury (OGI). If no OGI is suspected, IOP can be estimated using a two finger method. Using the index finger of each hand, gently apply alternating pressure on the globe through closed lids. There should be mild indentation of the eye with normal IOP (normal range, 10–21mmHg). With increased IOP, the globe will be much firmer when compared to the opposite eye, or the examiner’s own eye. The orbit around the eye may also feel tense in a retrobulbar hemorrhage.

A more detailed examination of the eye can be facilitated by the use of a direct ophthalmoscope for magnification. The examiner can use the plus lens dial (green or black numbers) to provide additional magnification. Details are found in Appendix B Use of the Direct Ophthalmoscope. Although deployed locations may have specific guidance against contact lens use, this may still be encountered. If a contact lens is clearly visible and accessible, it can be gently removed with forceps. Fluorescein will stain a contact lens, allowing for easy visualization.

4. MAINTAIN PATIENT COMFORT. PREVENT FURTHER DAMAGE.

Pain control is an important component of care in ocular injuries. Standard Tactical Combat Casualty Care (TCCC) pain control guidance applies to ocular injuries, including analgesic doses of ketamine if needed in systemic polytrauma. Additional guidance for pain control in PFC may be found in the CPG Analgesia and Sedation Management during Prolonged Field Care.3

Pain is not always present with serious eye injuries, and lack of pain should not be interpreted as lack of injury. Ocular injuries can cause a great deal of anxiety for patients, and this may affect care. A benzodiazepine may be added to the treatment plan for anxiety control and facilitation of care (diazepam 10 mg by mouth [PO] every 6 hours as needed).

A traumatized eye is highly susceptible to further damage; antiemetic medications are essential to prevent retching and increased pressure that can have significant effects on visual outcome.

Patching both eyes to decrease sympathetic eye movements has not been shown to improve visual outcome. Occluding both eyes will render the patient unable to move independently, may increase anxiety, and may put the patient and provider at increased risk in any PFC environment. The use of standard eye protection during patient transport can reduce the risk of further ocular injury or injury to the fellow eye. Eye protection can be used over a rigid shield to provide increased protection.

5. ESTABLISH CONTACT WITH EYE CARE CARE SPECIALIST. PRIORITIZE EVACUATION.

Determining the full extent of ophthalmic injuries and the resultant threat of permanent loss of vision is challenging without full ophthalmic training and equipment. All potential vision-threatening injuries should be evacuated with a goal of care by an eye surgeon within 24 hours. In some cases, with prompt teleconsultation or video consultation, it may be safe to delay evacuation to reduce the effect on the operational situation while providing necessary ophthalmic care. Evacuation within 24 hours is not possible in all situations; therefore, the goal of teleconsultation and forward care is to reduce morbidity and achieve the best possible outcome. In some operational environments, optometrists may be available to provide additional care or consultation closer to the point of injury.

Ocular examinations have many specialized components that a specialist may request. An example template with explanation can be found in Appendix C Basic Ocular Examination.