An 8 year old boy presents to the emergency department with moderately severe left eye pain 6 hours after riding his bicycle through some low hanging leaves from a tree. He didn't notice the tree branches until a few leaves hit him in the face. He has no bleeding wounds.
Exam: VS are normal. He does not want to open his left eye because of discomfort. Some anesthetic eye drops are instilled into his left eye. He complains that this burns a lot and he begins to cry. After 10 minutes (topical anesthetic usually works within minutes), he is able to open his eye. His visual acuity was 20/20 in the right eye and 20/30 in the left eye. His pupils are equal and reactive. His conjunctiva is slightly injected. No hyphema is visible. A drop of saline is placed on a fluorescein paper strip. This drop is then touched to his lower eyelid so fluorescein dye flows over the surface of his eye. With an ultraviolet light, a 0.5 cm linear abrasion is seen in the lateral aspect of his left cornea.
His eye is rinsed with saline to remove excess fluorescein. A single drop of a cycloplegic agent (such as homatropine) is instilled into his left eye. Antibiotic ointment is instilled into his eye and a pressure eye patch is applied. He is instructed to take over-the-counter analgesics for pain.
The next day he is checked by his primary care physician. The fluorescein exam is repeated and no corneal abrasion is seen. No further treatment is necessary.
The cornea is composed of three layers: the outer epithelium, the middle stroma and the inner endothelium. The outer epithelium is the only layer capable of regenerating. Injuries to the stroma and endothelium usually result in permanent scarring of the cornea, and reduced vision for the eye. Cornea has a high density of neuronal pain receptors, making injury to the cornea very painful.
Epithelial damage is commonly called corneal abrasion. The most common cause is external blunt trauma, such as foreign objects scratching the cornea. Other causes include chemical burn, thermal burn (such as welding and sun lamps), or prolonged exposure to ambient environment, such as decreased blinking and dry eyes, and contact lens wear. Occasionally, there is no history of trauma. Symptoms of corneal abrasion include pain, redness, photophobia, tearing, and foreign body sensation. Signs of corneal abrasion include conjunctival injection, or redness, swollen eyelid, and sensitivity to light. Occasionally, a visible irregularity of the corneal surface can be seen.
It is very important to document visual acuity when examining a patient with an eye injury. A topical anesthetic, such as proparacaine or tetracaine, can be instilled to decrease pain for the patient to facilitate the examination. Visual acuity should then be obtained and documented. Take note of any periorbital injuries, such as eyelid trauma, or possible orbital wall fractures. These separate injuries should be treated appropriately as well.
Ideally, an eye should be examined with a slit lamp for signs of corneal abrasion. Fluorescein is applied topically, and using cobalt blue light, the size, shape and location of the abrasion should be documented. Slit lamp examination is also helpful in determining if the injury involves deeper layers of the cornea, and possibly penetrating injury to the eyeball. Despite this advantage, most non-ophthalmologists use a plain ultraviolet light (Wood's lamp) with fluorescein to examine the cornea for abrasions. Eyelids are everted to look for foreign bodies.
The traditional treatment for corneal abrasion involves "pressure patching" the eye after topical cycloplegic and antibiotic drops or ointment are applied. The cycloplegic reduces the pain due to ciliary muscle spasm and the topical antibiotics provide prophylaxis against infection developing in the abrasion. A gauze eye patch is folded in half and placed over a closed eye. A second gauze eye patch is applied over the first eye patch, making sure the eye is completely closed. Paper tape is applied tightly over the patches from the forehead to the cheek. This type of treatment ensures that the epithelium can regenerate without having the eyelid abrading further on the corneal abrasion. Narcotic analgesics are sometimes necessary to treat the pain. The patches are left on 24 hours at a time, and the eye is reexamined for progress. Most corneal abrasions heal in 24 to 72 hours. If infiltrates are observed at any time, patching is discontinued and the patient needs to be treated for a corneal ulcer by an ophthalmologist.
A pressure patch is not recommended for abrasions which are at significant risk for infection, such as scratches from a tree branch, from a dirty fingernail, and abrasions in a contact lens wearer. These eyes are treated with every 1 to 2 hour applications of topical antibiotic ointment, until the abrasions heal completely. Eye patches are not always necessary and it is not possible to keep these on some young children.
Excessive ultraviolet light exposure to the cornea (and retina as well) can occur when observing a welding arc or flame, or with extremely bright sunlight exposure such as looking at the sun, during high altitude skiing (commonly called snow blindness), and occasionally at the beach. The welding arc produces invisible high intensity ultraviolet radiation which must be blocked by an ultraviolet light shield. Just as in a sunburn, patients with ultraviolet corneal burns do not notice much discomfort initially, but after 1 to 2 hours have passed, the burning sensation becomes very painful. Fluorescein examination reveals multiple, tiny pitting defects of the corneal surface, called superficial punctate keratopathy. Since this is usually a bilateral problem, bilateral eye patching is not usually feasible. Frequent topical antibiotic ointment is recommended and oral narcotic analgesics may be necessary for comfort. If only confined to the cornea, and not involving the retina, this problem is generally self limited.
A hyphema is defined as blood in the anterior chamber of the eye. It is usually caused by blunt trauma. The eye ball is compressed and it results in distortion of the iris and angle, thus causing tears in the iris and the angle vessels. It can present as a microhyphema, where only circulating red blood cells are present, or as a visible blood clot. The blood is generally reabsorbed by the trabecular meshwork over time. The greatest danger of hyphema is re-bleeding, which usually occurs between the 2nd and the 5th day after the initial injury. Re-bleeding is probably caused by clot retraction and fibrinolysis. Re-bleeds are associated with an increased incidence of glaucoma and decreased final visual acuity.
The management of hyphema remains controversial, but most experts agree that children should be placed on bed rest with bathroom privileges for at least 5 days and refrain from strenuous activities for 10 days. A fox shield (a metal shield) is also recommended to decrease the chance of further blunt injury in the early days. Topical corticosteroids, oral corticosteroid, and aminocaproic acid (anti-fibrinolytic agent) have all be advocated to decrease the incidence of re-bleeds. Occasionally, surgical evacuation of a blood clot is necessary to decrease complications, such as uncontrollable intraocular pressure, and corneal blood staining (permanent opacification of the cornea from infiltration of hemoglobin and hemosiderin).
1. An eye with a corneal abrasion should be patched if:
. . . . . a. it is associated with a corneal infiltrate.
. . . . . b. it has been scratched by a fingernail.
. . . . . c. it occurs in a contact-lens wearer.
. . . . . d. it is large and is in the center of the cornea.
2. A 4 year old boy was playing with sparklers on the 4th of July. He held it up high and his parents think that some sparks fell into his eye. He has some small blisters around his eyelids and he is complaining of intense eye pain. He refuses to open his eyes for an examination because of pain. Which of the following are possible options (more than one correct answer is possible):
. . . . . a. topical proparacaine as a single dose to facilitate an examination.
. . . . . b. intramuscular morphine to facilitate an examination.
. . . . . c. topical proparacaine now and p.r.n. at home for discomfort.
. . . . . d. acetaminophen with codeine syrup.
3. A 10 year old boy presents to the pediatrician with a red and teary eye for a day. He had been to a soccer practice on the day before presentation and the red eye began after that. The pediatrician does not see a corneal abrasion with fluorescein and sends him home with topical antibiotics. He still has the same symptoms the next day. What should the pediatrician do?
4. A 16 year old female presents to the primary care doctor with the complaint of bilateral red and painful eyes since waking up. She had forgotten to take off her soft contact lenses the night before because she was too tired. The primary care physician does not see any corneal abrasions but there are some small "white" dots in the corneas. What should be done?
5. A 4 year old boy presents to the emergency room with a red and painful right eye after a swing had accidentally hit the eye on the playground. On examination, he does not like to have the left eye covered because he "cannot see". The eyelids are swollen and ecchymotic and the conjunctiva has hemorrhages. The physician sees a blood clot covering 65 percent of the anterior chamber. What is the appropriate management?
1. Friedberg MA, Rapuano CJ. Wills Eye Hospital Office and Emergency Room Diagnosis and Treatment of Eye Disease. 1990, Philadelphia: J.B. Lippincott Company.
2. Orbits, Eyelids, and Lacrimal System. Basic and Clinical Science Course, Section 9., American Academy of Ophthalmology.
Answers to questions
1. Choice d is the correct answer. A corneal abrasion which is at significant risk for infection should not be patched. Choices a, b, and c are all at higher risk for infection.
2. Choices a and b are all reasonable answers. Choice d would be too slow for an office or emergency department, but it would be reasonable if one is willing to wait for it to take effect. Choice c is incorrect because topical ophthalmic agents should not be sent home with patients. Prolonged corneal anesthetic use often results in corneal complications because this blocks the eye's natural protection reflexes to minimize further corneal injury.
3. The differential diagnosis consists of corneal foreign body, conjunctival foreign body, early conjunctivitis. The eyelids should be flipped to look for small foreign bodies. If possible, the cornea should be inspected again with some magnifying glasses to look for a foreign body as well.
4. Whenever the cornea has white lesions, one should always suspect corneal ulcers or infiltrates. Overnight contact lens wear is the most significant contributor to the development of corneal ulcers in a contact lens wearer. The patient should be referred to an ophthalmologist as soon as possible and the patient should be advised to discontinue contact lens wear until treatment is completed.
5. The patient should have an ophthalmology consult as soon as possible. A metal shield should be placed on the eye, NOT a gauze eye patch (which can press on the eyeball), to decrease further chance of injuring the eye. He probably should be admitted to the hospital for bedrest and observation to decrease the chance of re-bleed.