A corneal abrasion is a painful scrape or scratch of the surface of the clear part of the eye. This transparent window covers the iris, the circular colored portion of the eye. The cornea has several layers that protect the eye. Some corneal abrasions may form a scar and permanently impair vision. A corneal abrasion is an injury (a scratch, scrape or cut) to the epithelium. Abrasions are commonly caused by fingernail scratches, paper cuts, makeup brushes, scrapes from trees or limbs, and rubbing the eye. Some eye conditions, such as dry eye, increase the chance of an abrasion. It is comprised of three layers and the membranes that separate these layers. It is very difficult to penetrate past the epithelium or top layer of the cornea. The cornea is normally devoid of blood vessels yet has many sensory nerves. When any trauma to the corneal epithelium occurs, cells are lost or destroyed and pain is immediately sensed. When a corneal abrasion occurs, the conjunctiva, or the white of the eye, turns red, as new blood vessels form and those present enlarge, in an attempt to increase blood flow to the eye as it attempts to bring to the eye those cells needed for the healing of the cornea. A corneal abrasion heals by the movement of neighboring epithelial cells, which slide over the wounded area, and through a cell division process called mitosis, which fill in the abraded area with new epithelial cells. Within two to three days of trauma to the cornea, these new cells start to adhere to the underlying membrane of the epithelium, called the basement membrane and within seven to eight days the abraded area usually heals completely without scarring.
Causes of Corneal Abrasion
The common Causes of Corneal Abrasion :
- Minor injury.
- Occurs when a foreign object is scraped across the cornea.
- Contact lenses.
- Blow to the eye.
Symptoms of Corneal Abrasion
Some common Symptoms of Corneal Abrasion :
- Tearing .
- Discharge of tears.
- Sensitivity to light.
- Eye pain.
- Blurred vision.
- Discomfort in the eye.
Treatment of Corneal Abrasion
- Antibiotic eye ointment, such as Polymyxin-bacitracin.
- Occlusion of the eyelid with a patch (keep the eye closed).
- Examination is done after using an anaesthetic.
- A 'patch' may be put on the eyes.
- Antibiotic used to prevent infection.
- Relief of pain with medication.
- At times, cycloplegic drops (paralyzes the ciliary muscle that controls the iris size).
- In selected cases, other medication such as steroids might be used.