Corneal erosion results from an injury on the cornea or from underlying dystrophy. It affects the cornea, the eye's clear, outermost, dome-shaped surface that covers the front of the eye.
The cornea consists of five layers among them the epithelium and Bowman’s membrane. The epithelium occupies the outermost layer. Corneal erosion occurs when the epithelium fails to stay correctly attached to the tissue below, including the Bowman’s or basement membrane. The epithelium breaks off easily with little effort. Corneal erosion that repeatedly occurs is called recurrent corneal erosion (RCE).
Also Known As
- Corneal abrasion
- Scratched eye
Causes and Risk Factors
It can occur suddenly and affect anyone. The following constitute the causes and risk factors associated with corneal erosion:
- Corneal dystrophies (abnormal changes in the structure of the cornea) such as Cogan dystrophy or map-dot-fingerprint dystrophy. Individuals at most risk usually have anterior basement membrane dystrophies.
- Previous corneal injuries (corneal abrasion) which may result from foreign objects, tree branches, fingernails and so on.
- People with dry eye syndrome, ocular rosacea and diabetes can develop RCE
- An ulcer on the eye from the herpes simplex infection
- Contact lenses that have not been handled hygienically or are ill-fitting
Signs & Symptoms
The following symptoms may present themselves in corneal erosion:
- Mild to severe pain especially in the morning. This is because the eyes dry up at night which causes the eyelids to get slightly attached to the epithelium. Also, the pain can last for a few seconds to days
- Lacrimation (abundant tears) especially upon waking up
- Sensitivity to light (particularly bright light)
- A feeling of something in the eye
- Blurred vision
- Dry eyes
- Redness of the eye
- The muscles around the eye may experience spasms resulting in squinting
The eye care professional may do the following to diagnose corneal erosion:
- A slit eye examination - In this exam, the professional uses an instrument to shine light into the eye. A bright light allows him/her to examine the front part of the eye thoroughly.
- Use of fluorescein to reveal the exact parts of the cornea affected by erosion. Fluorescein is a yellow dye.
Treatment of corneal erosion is directed towards ensuring the epithelium stays attached to the tissues below it.
The eye doctor may prescribe the following:
- Antibiotics for a few days until the epithelium heals
- Fit a patch on the eye or use a ‘bandage’ contact lens to keep the epithelium in place
- Preservative-free artificial tears to be used during the day to moisten the eyes
- A lubricating ointment to be used at bedtime to prevent the eyelid from sticking to the epithelium
- Oral pain relievers such as ibuprofen
- A combination of doxycycline and corticosteroids to help reduce frequent RCE
If lubricants and artificial tears don’t work such that the condition keeps recurring, the eye care professional may recommend surgery. Anterior stromal puncture is a type of surgery that works by creating tiny scars at the bottom of the epithelium. The surgeon uses a very fine needle to create the scars which force the epithelium to stick better on the layer underneath it.
Excimer laser phototherapeutic keratectomy, a laser treatment, may also be used to heal the epithelium.
A patient can do the following at home:
- Open the affected eye very carefully upon waking up. They should first open the good eye then lubricate the sick eye before slowly opening it
- Put a tight patch over the eye before bedtime. He/she should also put a patch upon waking up. The doctor will offer additional instructions on how to go about this
- Avoid rubbing the eye even if the eye feels fine
- Keep the eye shut as much as possible
- Use artificial tears to lubricate the eye
- Try to stay without contact lenses. Glasses can be won instead
- Use sunglasses to reduce sensitivity to light
Corneal erosion heals completely unless an individual has an ongoing corneal disease. However, it may take many years for total healing to occur.
If bacteria enter the eye through the epithelium, an infection may arise leading to a corneal ulcer. An ulcer is severe as it can lead to loss of vision. Also, corneal haze (cloud) and scarring may occur.
The patient will need a review after 24 hours or as directed by the eye care professional.
People can do the following to prevent corneal erosion:
- Use artificial tear ointment at night for as long as three months (to prevent RCE)
- Use protective eyewear especially during sports and so on
- Avoid situations that could lead to dry eyes such as smoking or working on a computer for long without taking a break and being in windy areas with no wraparound eye protection.