The cornea is the transparent, dome-shaped "window" that covers the front of the eye. A nick, scratch or scrape of the cornea is called a corneal abrasion. Corneal abrasions are one of the most common forms of eye injury. In some cases, they are caused by the direct impact of a sharp object, such as a pencil, staple, nail or sewing pin. They also can be caused by small, airborne particles, such as dust, sand or flying debris from soldering, woodworking or weed trimming. Even fingernails can cause a corneal abrasion.
- A history of eye trauma or prolonged wearing of contact lenses as well as typical symptoms suggest corneal abrasion. Staining the cornea with fluorescein stain confirms the diagnosis: The injured area appears green when examined with a Wood’s lamp or black light. Slit-lamp examination discloses the depth of the abrasion.
- Examining the eye with a flashlight may reveal a foreign body on the cornea; the eyelid must be everted to check for a foreign body embedded under the lid.
- Before beginning treatment, a test to determine visual acuity provides a medical baseline and a legal safeguard.
Your doctor will examine your eye with a light to check for any obvious corneal injuries, small specks of dust or dirt, or other foreign objects. To confirm the diagnosis of a very small corneal abrasion, your doctor may need to place a small drop of a yellow-orange dye called fluorescein into your eye. This dye will cause any area of abrasion to look greenish under a special blue light.
Usually, if you have only a mild corneal abrasion, you will not need any other tests. However, if your injury is more serious, your doctor may examine your eye with device called a slit lamp, and also test your vision.