Ultraviolet keratitis

Background

• Also known as photokeratitis, welder's flash, snow blindness
• Prolonged/excessive UV exposure to eyes leads to inflammatory response and subsequent desquamation of corneal epithelium leaving exposed nerve endings of cornea
• May not be initially apparent with latent period (6-12 hours) before onset

Causes

• Lack of proper eye protection
• UV exposure from:
  • Natural sources: snow, water, high altitudes (less protective ozone), eclipses
  • Artificial sources: Welder's arc, tanning beds, damaged metal halide lamps/lights

Keratoconjunctivitis Types

• Atopic keratoconjunctivitis
  • Common in patients with atopy (ie: eczema, allergies, asthma, rhinitis)
• Caustic keratoconjunctivitis
  • Secondary to chemical orbital exposure
• Epidemic keratoconjunctivitis
  • Highly contagious viral (adenovirus) conjunctivitis, associated with watery discharge
• Ultraviolet keratitis
  • Secondary to UV light exposure
• Keratoconjunctivitis sicca
  • Associated with autoimmune disorders such as Sjögren syndrome, sarcoidosis, rheumatoid arthritis, and scleroderma

Clinical Features

Slit Lamp Exam of UV Keratitis

• History of recent UV exposure - symptoms typically occur 6-12 hrs after exposure (will present late night/early AM)
• Symptoms include bilateral eye pain, foreign body sensation, lacrimation, blepharospasm, photophobia, chemosis, temporary decreased visual acuity
• Eye exam (including slit lamp)
  • Surrounding eyelid and face may appear mildly erythematous and edematous (consistent with sunburn)
  • Obvious tearing, discomfort, blepharospasm on exam with relief of symptoms after instilling topical anesthetic
  • Fluorescein exam - Superficial Punctate Keratitis - small, pinpoint areas of increased uptake on cornea
• Symptoms resolve spontaneously as cornea re-epithelializes over 48-72 hrs

Differential Diagnosis

• Other causes of keratoconjunctivitis
• Viral conjunctivitis
• Thygeson's Superficial Punctate Keratitis
• Dry eyes

High Altitude Illnesses

• Acute mountain sickness
• Chronic mountain sickness
• High altitude cerebral edema
• High altitude pulmonary edema
• High altitude peripheral edema
• High altitude retinopathy
• High altitude pharyngitis and bronchitis
• Ultraviolet keratitis

Evaluation

• Generally clinical diagnosis

Management

• Analgesia (very painful condition) - PO NSAIDS, opioids.
  • Do not prescribe topical anesthetics (i.e. tetracaine) to be used at home, this can lead to poor corneal healing and corneal melt
• Eye rest (avoid re-exposure)
• Lacrilube (saline eye drops)
• ± Antibiotic ointment (erythromycin ophthalmic or gentamicin ophthalmic)
• ± Cycloplegics

Disposition

• Discharge
  • Follow up with primary care provider in 1-2 days to ensure improvement of symptoms
  • Generally do not need ophtho follow-up given limited course
  • Emphasize proper eye protection with future exposure

See Also

• High Altitude Medicine
• Eye Algorithms (Main)
• Keratoconjunctivitis