What is the cornea?
The cornea is the front of the eye that is clear like a window and shaped like a dome over the coloured part of the eye. It has 5 layers, including a very thin superficial layer called the epithelium. This is the layer that often peels off when scratched.
What happens when there is a corneal abrasion?
When the cornea is scratched, the epithelium or top layer has essentially been peeled off. This causes temporary decreased vision and extreme pain.
How is a corneal abrasion treated?
A simple corneal abrasion is usually patched with a tight patch and antibiotic ointment. A dilating drop may also be used to decrease light sensitivity. The patch should be removed the next day and checked again by the eye doctor. If it is not completely healed it may be re-patched and rechecked then next day. Sometimes, the abrasion may take longer to heal. In this situation it is helpful to use a bandage contact lens. Your eye doctor can put this on your eye. You will not need to remove it for a few days. It is like a clear patch that you can see through. You will have to take antibiotic eye drops while wearing this bandage contact lens. If it falls out, you can just leave it out and see your eye doctor in follow-up. This bandage contact lens allows more time for the abrasion to heal.
Would I be able to see well again after the corneal abrasion is healed?
The short answer is YES. The cornea usually heals very well and you will be back to your normal state in 2-3 days after it has healed completely. However, if you have an infection on top of the scratch, or have delayed healing for various reasons, you may be left with irritation or a scar that might blur your vision (see below).
Why do some corneal abrasions take longer to heal? Will the scratch every come back?
If you suffer a corneal abrasion from a fingernail scratch, a tree branch, paper, or anything organic (i.e. that has carbon in it), this can cause poor healing especially for adults. These abrasions often take longer to heal and sometimes never heal properly. They may have little cysts under the top layer that can rip off months later when you first open your eyes in the morning. This causes "recurrent corneal erosion" that feels like the first time you got your eye scratched. To prevent these cysts from forming, you will have to use Muro 128 ® ointment at night for 4-6 months in your affected eye. This ointment is greasy and has a high level of salt in it. It causes the cysts to shrivel up and allows the top layer of the cornea to stick down properly. This ointment is available over the counter (you do not need a prescription for it).
If you are scratched by a contact lens, this scratch may be infected and may not be suitable for patching (because this may allow the infection to get worse). This type of scratch would have to be treated with frequent antibiotic eye drops and rechecked by your eye doctor frequently until it heals. You would not be safe to wear contacts again until specified by your eye doctor. If you have an infection that develops into an ulcer, this could lead to scarring and permanent loss of vision. Therefore, it is very important to be careful and treat these problems properly.
If you are diabetic, or have any nutritional deficiencies, you also may experience delayed healing of a scratched cornea. Extra vitamin C, good nutrition and hydration and controlled blood sugars would help the healing process.
