Superficial punctate keratitis is corneal inflammation of diverse causes characterized by scattered, fine, punctate corneal epithelial loss or damage. Symptoms are redness, lacrimation, photophobia, and slightly decreased vision. Diagnosis is by slit-lamp examination. Treatment depends on the cause.
Superficial punctate keratitis is a nonspecific finding. Causes may include any of the following:
Viral conjunctivitis (most commonly adenovirus)
Ultraviolet (UV) light exposure (eg, welding arcs, sunlamps, snow glare)
Systemic medications (eg, adenine arabinoside)
Topical medication or preservative toxicity
Peripheral facial nerve palsy (including Bell palsy)
Symptoms include photophobia, foreign body sensation, lacrimation, redness, and slightly decreased vision.
With viral conjunctivitis, preauricular adenopathy is common and chemosis may occur.
Keratitis that accompanies adenovirus conjunctivitis resolves spontaneously in about 3 weeks. Blepharitis, keratoconjunctivitis sicca, and trachoma
Ultraviolet keratitis
Ultraviolet (UV) B light (wavelength < 300 nm) can burn the cornea, causing keratitis or keratoconjunctivitis. Arc welding is a common cause; even a brief, unprotected glance at a welding arc may result in a burn. Other causes include high-voltage electric sparks, artificial sun lamps, and sunlight reflected off snow at high altitudes. UV radiation increases 4 to 6% for every 1000-ft (305-m) increase in altitude above sea level, and snow reflects 85% of UVB.
Symptoms are usually not apparent for 8 to 12 hours after exposure and last 24 to 48 hours. Patients have lacrimation, pain, redness, swollen eyelids, photophobia, headache, foreign body sensation, and decreased vision. Permanent vision loss is very rare.
Diagnosis is by history, presence of superficial punctate keratitis, and absence of a foreign body or infection.