What is Foreign Body Tracking?

(Picture of the Month. February 2002)

Picture from JS Andersen, et al. "A Handbook of Contact Lens Management." Vistakon, Johnson & Johnson Vision Products, May 1996.

This picture shows small scratches on the cornea, the front surface of the eye, caused by a foreign object in the eye. Eye care practitioners use a dye that glows with blue light in order to help see any surface disruption of the cornea. Foreign bodies may be sand, dirt, make-up, etc. In contact lens wearers, this is more often seen in rigid gas permeable (RGP) lenses. It is easier for materials to get underneath RGP’s, thus causing scratching and irritation. You will notice in the picture that the scratches are generally vertical. This is because of the mechanical action of the eyelids blinking and dragging the foreign body up and down.

If you are a contact lens wearer, what would you notice if you had a foreign body? Most likely, you would have the sensation that something was in your eye. You may feel mild to moderate (severe in some cases) pain. Your eye may be mildly red. You may experience tearing. If you feel you may have had a foreign body that caused some scratches, remove your contact lens. Use artificial tears, but avoid "get the red out" varieties of eye drops and do not use anyone else’s eye medications. Generally these scratches are superficial and resolve in about a day. If you have severe pain, lots of redness, decreased vision, or mucous discharge, contact your eye care professional. There are some instances where foreign body tracks can get infected, and antibiotic drops may be necessary.