Maxillofacial and Ocular Emergencies Study Guide for the CEN

Ocular

An ocular emergency is an emergency that affects the eye or associated structures, such as the ocular nerve. Examples that you encounter may include corneal abrasions, foreign bodies, burns, glaucoma, trauma such as globe rupture or laceration, retinal detachment, and eye ulcerations.

Corneal Abrasions

A corneal abrasion is a scratch or abrasion in the cornea, the clear layer at the surface of the eye. These abrasions can be triggered by anything that dries out or irritates the eye, such as a patient rubbing their eyes vigorously after anesthesia, wearing contact lenses too long, or getting a foreign body in the eye. Most abrasions heal within a few days, but larger or more severe abrasions will take up to a week to resolve.

Assessment

Symptoms of a corneal abrasion include sensitivity to light, squinting, tearing, difficulty opening the eye, and a sensation of sand in the eye or other scratchy sensations. The abrasion is diagnosed through a physical eye exam performed under a slit lamp, usually using fluorescein staining, to identify the abrasion. The doctor will also look for any foreign bodies that caused the abrasion and any associated infections.

Treatment

The treatment is to apply erythromycin ointment to prevent infection and ease discomfort and apply a soft gauze patch to the patient’s eye so that their eyelid remains closed for at least 24 hours post-injury. The eye can also be rinsed gently with sterile saline. Any foreign bodies should be removed if noted. Patients should be educated about lifestyle changes such as wearing safety glasses when appropriate, caring for contact lenses appropriately, and keeping eyes moist.

Burns

Ocular burns can be either thermal (due to heat exposure) or chemical in origin. Thermal exposure happens due to a house fire, bonfire, explosion, or fireworks-related injury. Chemical burns can be from caustic substances such as drain cleaner, ammonia, and bleach, or work-related chemical spills. Even seemingly benign hand sanitizer can cause an ocular burn.

Assessment

The patient will experience immediate severe eye pain, difficulty opening their eyes, and severely blurred or even absent vision if they can open their eyes (which depends on the extent of the injury). Their eyes will become watery and teary, their eyelids may swell, and they can have sensitivity to light, as well as redness in their eyes and eyelids. The doctor should take a comprehensive history to determine the cause of the ocular burn, which will guide treatment, and will perform a slit lamp exam to closely observe the eye’s surface. A fluorescein stain will highlight any corneal ulcers or abrasions. The patient’s intraocular pressure should be measured using a tonometer since it may be elevated due to inflammation or internal damage to the eye.

Treatment

In thermal burns, the damage stops as soon as the heat source is removed. In chemical burns, the damage continues until the chemical is removed. Keeping this in mind, the first treatment priority is to remove the chemical from the eye, which requires the eye to be flushed with water continuously for 10-15 minutes. Severe burns may require the eye to be flushed for 2-4 hours or until the pH of the surface of the eye is between 7.0 and 7.2. Many workplaces have different types of eye wash stations for initial rinsing. If present, contact lenses should be removed immediately. For mild injuries, a topical antibiotic ointment and artificial tears to moisten the eye are sufficient. In more severe injuries, the patient will receive topical steroids to lessen inflammation, topical cycloplegic agents to manage pain, and sometimes systemic pain medication in addition to the topical agents. Eye drops to reduce intraocular pressure, such as timolol, betaxolol, and dorzolamide, will promote corneal healing and prevent damage to the optic nerve.

Foreign Bodies

A foreign body is anything that gets stuck in the eye that isn’t supposed to be there. This can range from a fleck of dust to a piece of metal to an eyelash. If the foreign body remains in place, it can cause a corneal abrasion, ulcer, or even trigger an infection.

Assessment

The patient will notice a scratchy sensation or other discomfort in their eye, watering or tearing, redness, blurred vision, and light sensitivity. The provider will perform a comprehensive eye exam using a slit lamp exam and fluorescein staining to locate the object and check for any injuries to the cornea. Deep foreign bodies may need a head CT scan to be located.

Treatment

Many foreign bodies will work their way out without outside intervention as the eye waters and washes away the foreign body. Remind the patient not to rub their eye because it can worsen the irritation and possibly cause a corneal abrasion. The eye can be gently irrigated with lukewarm saline or water to flush out the object. Extremely large foreign bodies or those that have worked their way into the eye may require surgical removal under general anesthesia. When the object has been removed, the eye will usually heal well within a few days on its own.

Increased Intraocular Pressure

Increased intraocular pressure means that the pressure inside the eye is elevated. This can cause glaucoma, which damages the optic nerve and eventually leads to total blindness if left untreated. Previous eye injuries or surgeries, hypertension, diabetes, long-term use of steroids, or family history can all predispose a patient to developing increased intraocular pressure.

Assessment

Initially, increased intraocular pressure is often asymptomatic. Some patients report headaches, eye pain, or subtle changes in their vision like mild blurriness. As it progresses, the patient may notice vision loss and tunnel vision, meaning that their field of vision narrows and it looks like they are looking down a long tunnel at the little that they can see. Increased intraocular pressure is diagnosed by measuring eye pressure using a tonometer. Normal eye pressure is 10-21 mmHg and tends to increase slightly with age. Patients with slightly elevated intraocular pressure or other underlying risk factors should have their pressures checked at least annually.

Treatment

The first line of treatment to reduce intraocular pressure is prescription eye drops to decrease vitreous fluid production and increase fluid outflow. If medication is ineffective, surgical procedures may be needed. Options include a laser trabeculoplasty to create a new drainage pathway, laser cyclophotocoagulation to reduce fluid production in the ciliary body, tube shunt surgery to insert a small tube into the eye to improve drainage, and minimally invasive glaucoma surgeries (MIGS) that make tiny incisions in the eye to improve drainage and have a very short recovery process. Underlying conditions such as diabetes and hypertension that exacerbate glaucoma also need to be well controlled. Heavy lifting or head down yoga poses such as downward dog or inversions should also be avoided, as they can increase intraocular pressure.

Ocular Infections

An ocular infection is a bacterial, viral, or parasitic infection that affects the eye. The most common type of infection is conjunctivitis/pink eye, which is a contagious bacterial or viral eye infection. Allergens can cause eye irritation that appears similar but is not contagious. Other types of infection include keratitis (corneal inflammation), endophthalmitis (infection of the vitreous fluid),blepharitis (inflammation of the eyelid), uveitis (inflammation of the uvea), and orbital cellulitis, which impacts the eye socket and other tissue surrounding the eye.

Assessment

The patient’s eye can itch, burn, or sting, and both the eye and eyelids will look pink and irritated or bloodshot. The patient’s eye can have watery, yellow, green, or thick discharge. Their vision can become blurry, and their eyelids can stick together or become swollen, making them difficult to open. If the patient develops periorbital cellulitis, the area around the eye can appear red, warm, and swollen. The patient can also demonstrate sensitivity to light. An ocular infection is diagnosed using a slit lamp exam and fluorescein dye to reveal any defects in the cornea. A culture will be obtained from the eye and sent to see what pathogen (if any) grows, especially if the initial treatment is unsuccessful or the infection worsens during treatment. An MRI or CT scan can help to reveal the spread of infection, especially in periorbital cellulitis.

Treatment

Antibiotic ointments or eye drops are used to treat bacterial infections. Antiviral eye drops will be used to treat viral infections. Steroids can be used to reduce inflammation, but should be used sparingly to prevent masking any other underlying infections. Severe cases of orbital cellulitis may require admission to the hospital for IV antibiotics and potential surgical procedures to drain abscesses or remove infected/necrotic tissue. Ocular infections are particularly contagious among young children who touch their eyes and then touch common surfaces. Remind them to practice hand hygiene and minimize touching their eyes/face.

Retinal Artery Occlusion

Retinal artery occlusion is a sudden blockage in the arteries that supply blood to the retina. The light-sensitive layer at the back of the eye converts light into electrical signals that are transmitted to the brain via the optic nerve. If not treated immediately, it can lead to cell death and retinal damage that causes permanent vision loss. The blockage can be due to blood clots, cholesterol, or calcium.

Assessment

The most common symptom of retinal artery occlusion is sudden, painless, severe vision loss in one eye. Other symptoms include blurred vision, loss of peripheral vision, blind spots in the visual field, or a cherry spot seen in the retina during a dilated eye exam. Retinal artery occlusion is diagnosed using a fundoscopic (dilated) eye exam, optical coherence tomography (OCT) to take detailed images of the retina, and fluorescein angiography to evaluate blood flow to the retina.

Treatment

The primary treatment is to restore blood flow to the retina by removing the blockage from the artery. This can be accomplished by using a clot-dissolving medication such as tissue plasminogen activator (TPA). Hyperbaric oxygen therapy helps to supply extra oxygen to the retina and prevent permanent tissue damage. Releasing a small amount of fluid from the anterior portion of the eye also helps to restore blood flow. Conditions such as hypertension and diabetes can impair blood flow to the eye and need to be well controlled, especially if the patient has a history of retinal artery occlusion.

Retinal Detachment

A retinal detachment occurs when the retina pulls away from its usual position at the back of the eye. There are three types of retinal detachment: rhegmatous (vitreous fluid leaks from the eye through a tear in the retina and pushes it up), tractional (scar tissue pulls on the retina), and exudative (fluid leaks from the capillaries behind the eye and pushes the retina up). Prompt treatment is necessary to prevent permanent vision damage.

Assessment

The patient may notice:

• flashes of light, especially in their peripheral vision
• floaters or dark spots in their vision
• a dark shadow appearing over their vision
• sudden blurry vision

Retinal detachments are usually painless. A retinal detachment is diagnosed using a fundoscopic eye exam to closely examine the retina, optical coherence tomography (OCT) to take detailed pictures of the retina, fluorescein angiography to check retinal blood flow, and a visual acuity test.

Treatment

The patient should seek treatment immediately if they experience any of the symptoms listed above. The only treatment for a retinal detachment is a surgical repair, of which there are several different techniques depending on the nature of the tear. A cryopexy freezes the retina to seal tears. Laser therapy uses a laser to seal tears. Scleral buckling places a small belt around the eye to move the eye wall back. A vitrectomy is a procedure to remove vitreous fluid and repair the retina.

Ocular Trauma

Ocular trauma is any sudden traumatic injury that occurs due to an accident such as blunt force or a puncture. The most common types of traumatic injuries include hyphema (blood collecting between the cornea and iris), eye lacerations, penetrating injuries, and a globe rupture of the entire eyeball.

Assessment

Symptoms of ocular trauma include:

• sudden pain
• blurry vision
• double vision (diplopia)
• light sensitivity
• difficulty opening the eye
• ecchymosis around the eye or on the eyelid
• changes in pupil size and shape
• fluid leakage
• protrusion of ocular tissue
• visible blood between the cornea and the iris (a sign of hyphema)

Eye trauma is evaluated using a slit lamp exam, tonometer to measure intraocular pressure, visual acuity exam, fluorescein angiography to check ocular blood flow, and possibly a CT scan to evaluate damage to the tissues surrounding the eye (such as an orbital fracture).

Treatment

Minor ocular trauma can be treated with antibiotic ointment or drops to prevent infection, patching to reduce eye strain, and over-the-counter pain meds. More major trauma will need to be surgically repaired. The specific type of repair depends on the nature of the injury. A complete globe rupture may require a complete eye removal, also called an enucleation. After the surgical site has healed, the patient will be fitted for an eye prosthesis if they so choose for cosmetic purposes.

Ulcerations and Keratitis

The patient’s cornea can develop ulcerations and keratitis (inflammation of the cornea). Common causes of corneal ulcerations and keratitis include wearing contact lenses longer than recommended, infections (bacterial, fungal, or viral), eye dryness, or injury to the eye.

Assessment

Symptoms of corneal ulcerations and keratitis include:

• eye pain
• redness in the eye and eyelid or a bloodshot eye
• blurry vision
• tearing
• sensitivity to light
• difficulty opening the eye
• a watery eye
• swollen eyelids
• feeling like something is stuck in the eye

The conditions are diagnosed using a slit lamp exam, visual acuity test, fluorescein test, and pupil size and reactivity. Corneal scrapings can be taken if an infection is suspected to determine the best course of treatment.

Treatment

Infections are treated with the eye drops appropriate for the type of infection (antibiotics, antifungal medication, and antiviral medication, as warranted). Artificial tears will be used to moisten the eye and prevent dryness. The patient will need over-the-counter pain medication for pain relief. In severe cases, the patient may require a corneal transplant to restore their vision. Prompt treatment is key to preventing permanent damage and invasive options such as a corneal transplant.