Corneal Foreign Body
What is it?
Tiny particles that strike the eye at moderate speed often become embedded within the corneal surface.
The patient reports a feeling of gravel or sand in the eyeappropriately called the "foreign body sensation."
Tiny foreign bodies may be hard to spot without magnification provided by loupes or biomicroscope.
What to do?
- Instill a topical anesthetic in order to allow pain-free examination.
- Measure visual acuity.
- Inspect the cornea with penlight and loupe or biomicroscope magnification.
- If you see a foreign body, try to remove it first with a moistened cotton-tipped applicator. If you are unsuccessful, refer to an ophthalmologist unless you are skilled at using a need or other sharp instrument in this setting.
- One the foreign body is removed, stain the cornea by instilling fluorescein dye to check for epithelial erosions. Examine under cobalt blue light if possibleit enhances fluorescence.
- Evert the upper eyelid to rule out pre-tarsal foreign bodies.
- Instill a topical antibiotic and arrange follow-up examination in 24 hours to make sure the corneal abrasion has healed. Prescribe pain medication for that interval, as pain can be considerable, although short-lived. Patching is not necessary.
- Metallic foreign bodies often leave . Do not try to remove them; that may cause more damage. The rust usually disappears spontaneously within weeks.