Corneal Staining

Medically Reviewed by Whitney Seltman, OD on November 02, 2022
4 min read

Corneal staining isn’t a disease, it’s a sign of abrasions to your cornea, the outer surface tissue of your eyes. Abrasions can have different causes, including wearing contact lenses or if something gets stuck in or scratches your eye.

Corneal staining is also a term for a stain test that your eye doctor may use to look for cornea damage. This test uses a colorful (usually yellow) dye to highlight areas of damage on your cornea, as well as conditions like dry eye.

Contact lenses are a common cause of corneal abrasion. Whether you use contact lenses to correct your vision or to change how your eye color looks, they’re medical devices. Your eye doctor needs to prescribe them. They’ll talk with you about how to use, clean, and store them safely. If you do these things, you have a better chance of not having problems.

Damage is usually mild and heals fully and quickly. You may be more likely to have corneal staining if:

  • You don’t handle your contacts correctly when you put them in or take them out.
  • Your lenses fit too loosely or tightly on your eyes.
  • You wear your lenses for too long at a time.
  • Your lenses are dirty.

If you don’t keep your contact lenses moist, they can cause corneal damage. You alsoboost your risk of cornea infections or damage if you sleep in your contact lenses, even only now and then. Some types of lenses can be worn overnight while you sleep, but there’s still a risk of damage to your cornea. It’s better to take them out them before you go to bed at night or nap.

Tiny objects can get into your eye and damage your cornea: dust, sand, bits of wood or metal. You could scratch your cornea with your fingernail or by walking into a tree branch by accident. It feels gritty, your eyes tear up often, and you may have blurry vision or sensitivity to light.

Flush tiny objects out of your eye with saline solution or clean water, but don’t keep rubbing on it. If it keeps on bothering you, see your eye doctor for a fluorescein corneal stain test to show any corneal abrasion and to remove any objects in your eye.

Corneal staining is done by an eye doctor. They’ll place a special dye on the surface of your eyes. It highlights areas of damage to diagnose eye problems like these:

  • Dry eye
  • Sjögren’s syndrome, which often causes dry eyes
  • Scratches or abrasions on your cornea
  • Foreign objects stuck in your eyes
  • Cornea irritation from contact lens wear
  • Eye infections

How it’s done: First, you’ll take out your contact lenses or remove your eyeglasses. Your doctor will usually numb your eye and then blot your eye's surface with paper soaked with colored dye. You’ll blink a few times to spread the dye over your cornea.

Your doctor will shine a blue light at your eyes to look for any areas where there is corneal damage. The dye will make these areas look yellowish/green when the blue light shines on them.

Does the test hurt? This test may be uncomfortable if your eyes are very dry. Blotting paper feels scratchy as it touches your eyes. The dye could sting a little bit or slightly stain your skin, but those will go away quickly. Your doctor may use numbing drops to make the test more comfortable.

What test results mean: If you don’t have any abrasions, the stain floats on the cornea and doesn’t stick to your eye. If there is damage on your cornea, your doctor can rate it using a score or grade, usually from 0 (normal) to 5 (serious). Corneal abrasions in grades of 2 or lower may heal on their own.

Your doctor will take out any objects in your eye if that’s the cause. Don’t wear your contact lenses for several days while your eyes heal. It can take up to 5 days for a corneal abrasion to heal.

Your doctor may prescribe oral or eyedrop antibiotics, anti-inflammatory drops, or pain relievers. They may also place a bandage contact lens in your eye depending on the size and severity of the abrasion. 

Your doctor may check your eyes a day or two after you have a staining test to see if the stain is still there. If so, or you have developed a more serious infection or corneal ulcer, you may need to see an ophthalmologist, or eye specialist.

There are some things you can do to prevent corneal abrasions:

  • Clean and handle your contacts as your doctor instructs.
  • Don’t wear your contacts when you sleep.
  • Wear well-fitting contact lenses.
  • Keep your nails trimmed
  • Wear goggles during yardwork or home repair.
  • Remove low-hanging tree branches and other possible obstructions in your yard.