This is a test that uses orange dye (fluorescein) and a blue light to detect foreign bodies in the eye. This test can also spot damage to the cornea. The cornea is the external surface of the eye.
How Fluorescein Eye Stain Test is Performed
A piece of blotting paper containing the dye is touched to the surface area of your eye. You are asked to blink. Blinking spreads the color and coats the tear movie covering the surface area of the cornea. The tear film includes water, oil, and mucus to protect and oil the eye.
The healthcare provider then shines a blue light at your eye. Any problems on the surface area of the cornea will be stained by the color and appear green under the blue light.
The supplier can figure out the place and most likely cause of the cornea issue depending on the size, location, and shape of the staining.
- Your cornea is the clear surface area that covers your external eye. It’s made up of cells and proteins and is protected by tears.
- The cornea has two main functions: to secure the eye from irritants and to direct light as it enters your eye.
- A fluorescein eye stain test can help detect corneal injuries, little foreign objects or particles in the eye, and unusual tear production.
How to Prepare for the Test
You will have to eliminate your eyeglasses or contact lenses prior to the test.
How the Test will Feel
If your eyes are really dry, the blotting paper might be a little scratchy. The dye might cause a mild and short stinging sensation.
Why Fluorescein Eye Stain Test is Performed
This test is to:
- Discover scratches or other problems with the surface of the cornea
- Expose foreign bodies on the eye surface
- Determine if there is irritation of the cornea after contacts are recommended
Normal Results for Fluorescein Eye Stain
If the test outcome is normal, the dye remains in the tear film on the surface of the eye and does not stick to the eye itself.
What Abnormal Results of Fluorescein Staining Mean
Unusual results might point to:
- Unusual tear production (dry eye).
- Obstructed tear duct.
- Corneal abrasion (a scratch on the surface of the cornea).
- Foreign bodies, such as eyelashes or dust (eye – foreign object in).
- Injury or trauma.
- Severe dry eye associated with arthritis (keratoconjunctivitis sicca).
Risks During the Test
If the color touches the skin, there might be a slight, short, discoloration.