Corneal Abrasions Causes, Symptoms and Treatment

What Are Corneal Abrasions?

Corneal abrasions are the most common type of eye injury. They are scratches of the surface tissue of the eye, and can be very uncomfortable, even painful, and cause severe redness and sensitivity to light.

The cornea is a thin, clear lens located at the front and center of the eye. It's responsible for focusing light through to the retina at the back of the eye, where it is sensed, processed, and sent to the brain. Because the cornea is one of the few parts of the eye that are exposed to the air whenever the eye is open, it is at the most risk of injury.

Damage to the cornea can potentially affect vision, and requires proper medical attention in order to heal properly and limit any permanent damage. If not treated properly, or if the damage is serious enough, the chances of visual impairment or blindness in the injured rise significantly.

What Causes Corneal Abrasions?

A corneal abrasion can happen in many different ways. If the surface of the eye is scratched or otherwise damaged by any foreign object, big or small, the injury to the eye is called a corneal abrasion 

While new and original ways of being injured are always being discovered by the unlucky, the common methods of sustaining a corneal injury include walking into low-hanging tree branches, getting small particular matter like sand or sawdust in the eye, and various types of horseplay, such as wrestling with a pet dog, or having a pillow fight.

Some corneal abrasions occur during a major accident, such as shards of glass entering the eye during a car collision. Others are far less dramatic, a mild eye itch might cause a person to rub their eye, which turns a small speck of annoying matter into an instrument of torture. As the small particle is rubbed into the eye, it creates shallow but painful scratches.

Little protection is offered by contact lenses, which are thin and delicate. All but the tiniest of threats would likely penetrate the lens, and possibly even get trapped between the lens and the surface of the eye, making matters even worse.

What Are The Symptoms Of A Scratched Cornea?

The seriousness of corneal abrasion can vary from minor irritation to a more serious medical condition, if you experience any or all of the symptoms below you should seek prompt medical assistance,

• Pain
• Discomfort
• Redness
• Excessive tearing
• Sensitivity to light
• Headache
• Blurred vision

If there's any chance that you may have a corneal abrasion, it's important to seek emergency medical treatment immediately. Microorganisms such as Acanthamoeba have been found in tap water and even bottled water, and these pathogens can cause a serious, vision-threatening infection if introduced to an eye with a scratched cornea, if left untreated a corneal abrasion can become infected and lead to a corneal ulcer.

What Is The Treatment For A Scratched Cornea?

If you think you may have a scratched cornea there a few things you can try at home to remove the foreign object

DO

• Rinse your eye with saline solution
• Remove your contact lenses if appropriate
• Pull your upper lid over your lower lid - this may help to dislodge any foreign object
• Blink slowly several times - this can help to remove small irritants
• Take over the counter pain medication like Paracetamol

DO NOT

• Try to remove an object embedded in your eye
• Touch or rub your eye
• Wear contact lenses
• Wear makeup
• Apply an eye patch - the dark, sealed environment will promote the growth of bacteria, and increase the risk of infection

If the feeling doesn't go away, or if it worsens, then seek medical attention as soon as possible. Minor abrasions sometimes can be treated with non-preserved lubricating drops to keep your eye moist and comfortable while your eye's natural healing process takes place.

The NHS has some great advice on how to treat an eye injury at home or when to go to your GP or A&E

To diagnose a corneal abrasion, a doctor will use several different eye drops. The first drops will numb the eye and will provide a great deal of relief for the time being. Next, drops that glow under specific kinds of light are used, which may temporarily alter vision. The colouring used glows brightly under ultraviolet light, but only has a mild tint under normal lighting. From the patient's perspective, there may be a yellow or orange tint to everything seen through that eye for a short time.

Each instance of a scratched cornea is different, and using his or her professional judgment, the doctor may choose to take a swab sample from the eye and test it for a bacterial infection. Even without this test, it's very likely that antibiotic eye drops will be used as a precautionary measure. They will help to fight any bacteria that may be currently present in the wound, as well as prevent any from developing as it heals. Steroid drops may be needed, which will reduce inflammation, and help prevent scarring. Pain management is also addressed, either through topical Non-Steroid Anti-Inflammatory Drugs (NSAIDs), or standard over the counter pain medication such as Paracetamol.

Contact lenses should not be worn while recovering from a scratched cornea. Not only might the lens cause undesired irritation of the wound, it may also introduce and harbour bacteria. Your eye doctor will advise you when can begin wearing your contact lenses again.

Mild corneal abrasions, especially those treated quickly, are likely to heal with no permanent scarring or changes in visual acuity. However, more serious abrasions, especially those directly in front of the pupil, might have lasting effects.

It's likely that your doctor will recommend a follow-up visit to monitor the healing process. It may be as soon as the next day, or it may be later in the week. The importance of this appointment should not be underestimated. Not all corneal abrasions will heal properly, even after an initial doctor's visit. Catching these issues quickly provides an opportunity to correct the problem before it's too late.

Untreated corneal abrasions are likely to develop an infection and may lead to a corneal ulcer. In this scenario, severe or total vision loss is possible.

How to Prevent a Scratched Eye

Although many causes of corneal abrasions are difficult to prevent, others can be avoided by taking some simple, common-sense precautions, for example, always wearing safety glasses or protective goggles in work environments with airborne debris, particularly in welding environments. Likewise, protective eyewear should be used when doing yard work, using power tools, and playing sports. Be aware, when pruning trees and shrubs, or picking fruit from a bush, it is very easy to get poked in the eye with a branch. 

When wearing contact lenses, always follow the instructions for care and handling offered by your Optometrist and make sure that the finger that you use for insertion has the nail kept trimmed and is smooth.