What is it?
Keratitis is an inflammation of the cornea caused by infection, trauma, dry eyes, ultraviolet exposure, contact lens overwear, or degeneration.
Keratitis often begins with . You can usually spot it by seeing that the light reflection in the affected region is hazy and broken up.
Fluorescein staining is a big help because it turns areas of green. A cobalt blue filter .
Once the inflammation extends beneath the epithelium, the healing process will leave a .
A common cause of infectious keratitis is herpes simplex, which produces a . It must be treated promptly with topical (trifluorothymidine or adenine arabinoside) or oral (acyclovir, valacyclovir, famciclovir) anti-viral medications to prevent penetration into the deeper layers. Deep infection typically leads to or loss of tissue (ulceration). Then there is a threat of corneal perforation and infection inside the eye (endophthalmitis).
How does it present?
Symptoms of keratitis are blurred vision, photophobia, periocular pain, and foreign-body sensation. The conjunctival blood vessels are dilated most intensely around the edge of the cornea . But there may be surprisingly little redness. If white cells invade an infected cornea, you will see a instead of a transparent cornea.
What to do?
Do not attempt to treat. Refer emergently because of the complexity of diagnosis and the importance of specific treatment to prevent permanent loss of vision.