What is a Corneal Abrasion?
The cornea is the clear front window of the eye. It covers the colored portion of the eye, the iris, much like the glass of a watch covers its face. The cornea is made up of five layers. The outermost layer is called the epithelium.
A corneal abrasion results from a disruption or loss of cells in the epithelium. Abrasions are painful. Common causes of abrasions include problems from contact lenses, fingernails, paper cuts, tree or brush limbs, makeup brushes or rubbing the eye. Many corneal abrasions aren’t caused by a noticeable traumatic event, such as getting poked in the eye. Sand, dust and other small particles can cause a corneal abrasion as well, especially if you rub your eyes. There are some conditions, such as dry eye, that may make injury more likely. If your eyes dry out while you are sleeping, your eyelids may stick to your cornea. When you wake up and open your eyes, your lids can tear and pull off a portion of the epithelium, causing a painful abrasion.
The corneal surface usually heals within a day or two, but the eye may be very uncomfortable while healing. The cornea is one of the most sensitive parts of your body, so even a very small abrasion can be extremely painful and feel much larger in size.
Signs and Symptoms of a Corneal Abrasion:
Pain
Redness
Light sensitivity
Tearing
Foreign body sensation
Blurred vision
Dull ache or headache
What Causes a Corneal Abrasion?
Something hitting or blowing into the eye
Foreign matter getting stuck under your eyelid
Sports injuries
Improperly fitted or maintained contact lenses
Something poking you in the eye
Rubbing your eyes vigorously, especially if there could be something in the eye
Certain eye conditions
Undergoing surgery under general anesthesia
Treatment:
People have a tendency to rub their eyes when they feel like something is in them, but this can make matters worse. If you get something in your eye, you can attempt to flush it out with sterile saline eye wash, but don’t rub your eye. If you think that you have scratched your eye, it is safer to use sterile saline or multipurpose contact lens solution rather than water. Microorganisms such as Acanthamoeba can be found in tap water, and these can cause serious vision-threatening infections if introduced to an eye with a scratched cornea. After flushing the eye if pain and foreign body sensation continue, seek immediate attention because corneal abrasions can cause serious harm in as little as 24 hours.
Treatment varies dependent upon the severity of the abrasion and the cause. Minor abrasions may simply need lubricating drops to keep the eye moist and comfortable while it heals. As a precaution, abrasions are often treated with an antibiotic eye drop or ointment to prevent infection. Superficial or small abrasions will often heal within a day or two.
Larger abrasions may require a bandage contact lens. This will prevent the eyelid from moving over the healing epithelium while blinking. These lenses provide pain relief and sometimes speed healing. Another common treatment is repeated application of lubricating ointment to the eye, which forms a soothing layer between the inner eyelid and the abrasion. Sometimes a dilating drop is used to help with pain associated with light sensitivity. Often additional lubrication is helpful throughout the day until discomfort has disappeared. Some diseases such as dry eye disease and diabetes may slow the progression of healing. Large, deep corneal abrasions may take longer to heal and can cause permanent scarring that might affect healing. When treated properly, most corneal abrasions result in full recovery. Compliance with follow-up appointments is very important, because corneal abrasions don’t always heal properly and can lead to recurrent corneal erosions and other complications that can affect your vision.
Prevention:
Safety Glasses or Protective Goggles
Proper contact lens care
Treat dry eye or other underlying conditions that may lead to an abrasion
What is a Corneal Erosion?
A corneal erosion occurs when the epithelium does not stay attached correctly to the corneal tissue below. If the problem occurs repeatedly, it is called a recurrent corneal erosion. Often symptoms will occur in the morning when you first open your eyes. The eyes get naturally dry at night and the eyelid can stick to the epithelium. If the epithelium is not firmly attached, the lid can cause the epithelium to tear off. Without treatment, this can be a chronic problem.
Signs and Symptoms of a Corneal Erosion:
Mild to severe pain, often worse in the morning upon waking
Redness
Light sensitivity
Tearing
Dryness
Foreign body sensation
Blurred vision
Who is at Risk for Corneal Erosion?
Corneal Erosion can occur spontaneously to anyone. Certain factors may increase the risk:
History of eye injury
Presence of a corneal disease, such as a corneal dystrophy
History of a corneal ulcer
Wearing contact lenses that are improperly fitted or cared for
Treatment:
Recurrent corneal erosions can be stubborn and frustrating. Due to the nature of the condition and resistance to common therapies, follow-up care is crucial. Patients are assessed on a case-by-case basis to create an individualized treatment plan.
Lubrication
Lubricating drops and ointments are key to ending the erosion cycle. Frequent use of preservative-free artificial tear combined with a lubricating ointment at bedtime will help prevent the eyelid from sticking to the corneal epithelium.
Salt containing solutions or ointments (Muro 128)
Draws fluid out of the cornea to reduce swelling.
Punctal Occlusion
Especially useful for chronic dry eye patients. A small silicone plug is placed in the tear duct opening of the lid to promote more rapid healing and prevent further attacks by increasing the time our natural & artificial tears remain on the surface of the eye.
Bandage Contact Lens
An extended wear soft contact lens may be placed in the eye for an extended period of time (2-8 weeks) with a prophylactic antibiotic. In one study, 75% of patients who received a BCL had no recurrence of erosion for one year after treatment.
Combination Therapy
Another study showed that patients treated with topical lubrication, oral tetracyclines (ie. Doxycycline), and a topical steroid eyedrop for three weeks demonstrated a decrease in pain, improvement in vision, and no recurrence of erosion during a follow-up period of two years. Both tetracyclines and topical steroids are believed to aid in the recovery and reattachment of the corneal epithelium.
Surgical Options
Surgical options are generally reserved for patients who have failed all of the above treatments.
Anterior stromal micropuncture: creates tiny scars at the base of the epithelium with a very fine needle. This scarring acts as an anchor for the epithelium to adhere better to the corneal layer beneath it.
Debridement and superficial keratectomy: methods used to remove the top layer of the cornea in the hope that the new epithelium that grows back is stronger and better adherent.
Phototherapeutic keratectomy: an excimer laser is used to remove a portion of the corneal layer beneath the epithelium. Like the above methods, this allows the cornea to re-epithelialize with stronger adhesion to the underlying layers.
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