The cornea is the clear multi-layered outer part of the eye that protects the eye from foreign particles and assists with proper vision. When something does get into the eye, it can scratch and penetrate the cornea, causing corneal abrasion which can be very uncomfortable and painful. These types of injuries are normally quick to heal but should be treated immediately by a physician to reduce the risk of infections and permanent damage occurring.
Definition & Facts
By definition, a corneal abrasion is simply a scratch or abrasion of varying severity. It can be minor with penetration only along the first layer of the cornea. In more severe cases, the scratch can go deeper into the cornea and through its bottom two layers which greatly increases the possibility of scarring on the eye.
Even a very minor abrasion to the eye can be very painful and irritating. Statistics show that approximately 10 percent of emergency care for eye related problems is directly associated with corneal abrasions. More men are treated for these injuries as compared to women and children.
Symptoms & Complaints
Swelling and inflammation of the eye are also possible. Other individuals have complained of increased sensitivity to light which contributes to blurred vision or loss of visual acuity. Headaches and uncontrollable ocular twitching may also occur. Nausea due to pain is an additional symptom of these types of injuries, though this is a rarer occurrence.
In small children, it may be hard to determine the presence of corneal injury with the common symptoms. Increased fussy behavior may be the only clue among small, nonverbal children so consulting a pediatrician is necessary. It is important to note that symptoms may not occur immediately. In some cases, they only appear a few hours after the actual injury.
There are many circumstances that can lead to the accidental injury of the cornea. Children are more likely to wound their cornea during play time, and the workplace is the most common area adults suffer this type of injury. Here are the most common causes of corneal abrasions:
- Being poked in the eye - by fingernails, pens, makeup applicator, children, etc.
- Foreign object blown into the eye such as sawdust, dirt, ash, leaves, grass and sand
- Vigorous rubbing of the eye with or without the presence of a foreign body
- Misuse and improper care of contact lenses
- Failure to use eye protection such as googles when working with wood and metals.
Other causes, though more uncommon, can include exposure to ultraviolet radiation, inverted eyelashes, and certain types of eye infections. Improper care of the eyes during surgery under general anesthesia can lead to the drying out of the cornea which also raises the risk of abrasions.
Diagnosis & Tests
Once any of these symptoms are experienced, it is important to consult a physician immediately to reduce the risk of scarring and permanent damage to the eye. To confirm corneal injury, the practitioner will do a thorough eye examination that includes placing a drop of numbing anesthetic combined with yellow dye into the wounded eye. Pain commonly subsides with the eye drop, providing almost immediate relief.
The physician will observe the eye under a biomicroscope or slit lamp. If the yellow dye leaks into the eye itself, the cornea abrasion has been confirmed. This process will also help determine the size, intensity and location of the abrasion.
To rule out the presence of an external object in the eye, an X-ray may be performed. Rarely will an MRI be used. Depending on the severity of the injury, referral to a corneal specialist for further testing may be necessary to determine the need for more further treatment.
Treatment & Therapy
The severity of the corneal injury will determine the best treatment options available. In the small and shallow corneal abrasions, the only needed treatment may be application of medicated eye drops a few times a day for around a week.
When a bacterial infection is present in the eye, the practitioner will likely prescribe a specific antibiotic drop for the particular infection. The pain associated with corneal abrasions can be treated with prescribed eye drops and over-the-counter oral medications such as aspirin. Patients who wear contact lenses are also recommended to wear glasses, and must consult their physician before returning to using contacts to make sure the injury has completely healed.
If severe penetration and wound to the cornea has occurred, surgery may be the only treatment to prevent scarring and vision loss. Ordinarily, common corneal abrasions will heal without complication within a week when cared for properly.
Prevention & Prophylaxis
One should always wear the recommended protective eye gear when working with welding equipment, saws, sanders and other construction equipment. If a foreign object enters the eye, it is advised not to rub the eye. Children should be taught not to touch their own or others' eyes.