Corneal Abrasion Treatment & Management

Corneal abrasions heal with time. Prophylactic topical antibiotics are given in patients with abrasions from contact lenses. Traditionally, topical antibiotics were used for prophylaxis even in noninfected corneal abrasions not related to contact lenses, but this practice has been called into question.

Patching the eye has been used to help relieve the pain associated with corneal abrasion, but research has not shown benefit from patching.^{[20, 21, 22]} Patching should not be performed in patients at high risk of infection, such as those who wear contact lenses and those with trauma caused by vegetable matter, because of potential incubation of infecting organisms and promoting subsequent infectious keratitis.

Some ophthalmologists advocate the use of diclofenac (Voltaren) or ketorolac (Acular) drops with a disposable soft contact lens in addition to antibiotic drops.^{[23, 24, 25]} This therapy may be an effective alternative to patching, as it allows the patient to maintain binocular vision during treatment and reduces inflammation.

Patients with all but the most minor abrasions usually require a strong oral narcotic analgesic initially. In addition, topical cycloplegics may be required to relieve pain and photophobia in patients with large abrasions until their healing is nearly complete.

Emergent ophthalmologic consultation is warranted for suspected retained intraocular foreign bodies. Urgent consultation is needed for suspected corneal ulcerations (microbial keratitis).

Routine use of topical antibiotics for corneal abrasions remains controversial. Many emergency physicians have stopped using these agents for minor injuries, though others still treat corneal abrasions with broad-spectrum antibiotic ointments for lubrication and infection prophylaxis. Antibiotic use persists despite its unproved effectiveness and despite evidence that ointments may retard corneal epithelial healing.

Although use of prophylactic antibiotics after trauma or surgery is sometimes discouraged in general medicine, ophthalmologists use topical antibiotics for corneal abrasions because de-epithelialized cornea is more susceptible than intact cornea to infection, especially if the eye is patched. The injured cornea is vulnerable not only to pathogens contaminating any foreign body that produced the abrasion but also to potential pathogens present in the normal conjunctival flora.

Antibiotics should be continued until the patient is asymptomatic.

To the authors' knowledge, no randomized double-blind placebo-controlled trials have been conducted to evaluate the advantage of prophylactic antibiotics for noninfected corneal abrasions. Because the incidence of microbial keratitis in this setting is low, such a study is unlikely. The estimated annual incidence of ulcerative keratitis is 0.13-0.21% for people who wear extended-wear soft contact lenses and 0.02-0.04% for those using daily-wear soft contact lenses.

Fluoroquinolones (eg, ofloxacin) are probably the most common agents used for prophylaxis with corneal abrasions because of their broad-spectrum coverage and low toxicity and because of the low resistance of commonly acquired organisms to these drugs. In addition, fluoroquinolones have proven efficacy in the treatment of bacterial corneal ulcers. Prolonged and low-frequency dosing should be avoided to discourage the emergence of resistant organisms due to subinhibitory antibiotic concentrations on the ocular surface.

Ofloxacin has effectiveness similar to that of tobramycin for external ocular infection, fortified cefazolin and tobramycin for bacterial keratitis, and fortified gentamicin and cefuroxime for microbial keratitis. Trimethoprim also provides good broad-spectrum coverage and is an excellent prophylactic agent. A combination drop of polymyxin and trimethoprim is commercially available.

For large or dirty abrasions, many practitioners prescribe broad-spectrum antibiotic drops, such as trimethoprim/polymyxin B (Polytrim) or sulfacetamide sodium (Sulamyd, Bleph-10), which are inexpensive and least likely to cause complications. Alternatives are an aminoglycoside or a fluoroquinolone.

Abrasions due to contact lenses warrant antibiotic treatment because of their propensity to become infected corneal ulcers. Coverage for gram-negative organisms (especially Pseudomonas species) with agents such as gentamicin (Garamycin), tobramycin (Tobrex), norfloxacin (Chibroxin), or ciprofloxacin (Ciloxan) is recommended.

Antibiotic drops are more comfortable than ointments but must be administered every 2-3 hours. Antibiotic ointments (eg, bacitracin, polymyxin/bacitracin, erythromycin, ciprofloxacin) retain their antibacterial effect longer than drops and thus can be used less often (every 4-6 h), but they are more uncomfortable because they can cause visual blurring. Ointments are frequently used in children whose crying washes out the drops.

For topical use, the sterile powder is reconstituted by adding 20-50 mL of sterile water for injection or 0.9% sodium chloride solution for injection to a vial containing polymyxin 500,000 U. This mixture creates a solution with a polymyxin concentration of approximately 10,000-25,000 U/mL (10,000 U = 1 mg).

Avoid antibiotics containing neomycin (eg, Neosporin) because of the high incidence of allergy to neomycin in the general population. The use of prophylactic periocular injections or systemic administration of antibiotics after corneal abrasions is controversial.

The pain of corneal abrasions may be severe and should be treated with nonsteroidal anti-inflammatory drops and, if necessary, a soft bandage contact lens. Narcotic analgesia is occasionally required on a short-term basis. These are continued until the pain decreases to the point that it can be managed with over-the-counter analgesics.

Instillation of a long-acting cycloplegic agent can provide significant relief for patients with marked photophobia and blepharospasm. These agents relax any ciliary muscle spasm that may cause a deep, aching pain and photophobia. Cycloplegic agents are mydriatics; therefore, to prevent an episode of acute angle closure glaucoma, ensure that the patient does not have narrow-angle glaucoma.

Small abrasions can be managed on an outpatient basis. Ice compresses should be used for 24-48 hours to reduce edema. Warm compresses can be used thereafter.

Inform patients about the signs of wound infection, including increasing pain, erythema, edema, and purulent discharge. This helps in making the decision for early antibiotic intervention.

Patients must be informed about the signs and symptoms of complications, such as foreign body sensation, conjunctival injection, and decreased vision, so that treatment can be initiated promptly.

Flynn et al conducted meta-analysis of several studies of patching for corneal abrasions.^[26] Six groups had evaluated pain; 4 found no difference, whereas 2 favored not patching. Complication rates did not differ between use and no use of patches.

Flynn et al noted, "Eye patching was not found to improve healing rates or reduce pain in patients with corneal abrasions. Given the theoretical harm of loss of binocular vision and possible increased pain, the route of harmless nonintervention in treating corneal abrasions is recommended."^[26]

Although the use of slowly dissolving lenses made of porcine collagen is an excellent concept, this treatment is not widely used. A therapeutic lens that dissolves after 1-3 days is appealing, but most clinical indications require use of the lens for more than 3 days. An exception might be an uncomplicated corneal abrasion in which a collagen lens could be an alternative to a pressure dressing.

One study showed that, with common corneal abrasions, collagen lenses resulted in unexpected discomfort rather than decreased symptoms. In most applications, collagen lenses have failed to find acceptance because of their expense, induced discomfort, difficulty in handling, and lack of optical clarity. Furthermore, the lenses must be constantly replaced in applications in which more than 3 days of wear is required.

Another study demonstrated that collagen lenses were not helpful in healing persistent epithelial defects after penetrating keratoplasty.^[27]

Persons who work in high-risk occupations such as auto mechanics, metalworkers, or miners should wear protective eyewear. People who participate in contact sports such as hockey, lacrosse, or racquet sports such as squash or racquetball should always wear protective eyewear. Eye protection is also important for patients whose work or recreation increase the risk of corneal abrasion or ultraviolet light exposure (eg, farming, hiking through areas of tall foliage, skiing).

To prevent corneal abrasion in patients who are unconscious or who cannot voluntarily close their eyelids (eg, because of Bell palsy or other neuropathies), tape the eyelids closed.

Patients who wear contact lenses should make sure they fit properly and change them accordingly.

Close follow-up care of corneal abrasions is necessary because of the danger of the abrasion progressing to an ulcer. Essentially all corneal ulcers begin with an abrasion. Abrasions resulting from vegetable matter are at high risk for fungal ulcers. Abrasions resulting from contact lens wear should be monitored for Pseudomonas infection and amebic keratitis.

Patients with abrasions should receive follow-up care until healing is complete and the fluorescein stain is negative, to confirm that a corneal ulcer has not developed. However, minor abrasions should heal within 24-48 hours and do not require follow-up if the patient is completely asymptomatic at 48 hours. Reexamine large abrasions frequently until reepithelialization occurs and the potential for infection no longer exists.

Advise eye rest (ie, no reading or work that requires substantial eye movement that might interfere with reepithelialization). Advise patients to avoid bright light or to wear sunglasses for comfort if they have notable photophobia.

Patient with corneal abrasions that do not resolve with the use of routine prophylactic antibiotics must be evaluated for conditions that impede healing; examples are infection, neurotrophic keratopathy, and topical anesthetic abuse.