Recurrent Corneal Erosion
A pterygium is a mass of fleshy tissue that grows over the cornea (the clear front window of the eye). It may remain small or may grow large enough to interfere with vision. A pterygium most commonly occurs on the inner corner of the eye, but it can appear on the outer corner as well.
The exact cause of pterygia is not well understood. They occur more often in people who spend a lot of time outdoors, especially in sunny climates. Long-term exposure to sunlight, especially to ultraviolet (UV) rays, and chronic eye irritation from dry, dusty conditions seem to play an important role. Dry eye also may contribute to pterygium.
When a pterygium becomes red and irritated, eyedrops or ointments can be used to help reduce the inflammation. If the pterygium grows rapidly or is large enough to threaten sight, it can be removed surgically.
Despite proper surgical removal, a pterygium may return, particularly in young people. Protecting the eyes from excessive ultraviolet light with proper sunglasses, avoiding dry, dusty conditions, and using artificial tears can also help.
A pinguecula is a yellowish patch or bump on the white of the eye, most often on the side closest to the nose. It is not a tumor but is an alteration of normal tissue resulting in a deposit of protein and fat. Unlike a pterygium, a pinguecula does not actually grow onto the cornea. A pinguecula can also be a response to chronic eye irritation or sunlight.
The cornea is the clear front window of the eye. It covers the iris (the colored portion of the eye) and the round pupil. The cornea is composed of five layers. The outermost layer is the epithelium.
When the epithelium does not adhere correctly to the corneal tissue below, this can cause a condition called recurrent corneal erosion.
There are many possible causes of recurrent corneal erosion, including a history of corneal injury, such as corneal abrasion, and corneal disease.
- severe pain (often upon waking);
- light sensitivity;
- blurred vision;
- red eye;
- dryness; and
Often symptoms are first noticed upon waking in the morning. This is because when you open your eyes, your eyelids pull away the cells that have been loosened overnight. Without treatment, your eye may continue to experience this erosion.
To detect and evaluate corneal erosion, your ophthalmologist (Eye M.D.) will instill eyedrops with green dye in your eye and examine your eyes using a slit-lamp microscope. Your ophthalmologist may prescribe saline solution drops to help your epithelium adhere to the underlying tissue, and he or she also may ask you to use artificial tears to keep your eyes moist.
For patients with corneal erosion caused by corneal disease, an additional procedure may be necessary to remove the epithelium or adhere it to the underlying tissue in order to encourage a better bond.
Should you continue to experience recurrent corneal erosion despite conservative treatments, your ophthalmologist might suggest an additional procedure called a phototherapeutic keratectomy to remove a layer of corneal tissue with a laser. This technique is used to promote healing and good adherence of the epithelium.
No treatment is necessary unless the pinguecula becomes inflamed. A pinguecula does not grow onto the cornea or threaten sight. On rare occasions, a pinguecula can be surgically removed if it is particularly annoying.