photokeratitis

Photokeratitis is a painful corneal epithelial injury caused by exposure to ultraviolet (UV) radiation. It is a form of ultraviolet keratitis and is commonly described as snow blindness or welder’s flash when related to specific exposures. UV-A and especially UV-B light from sunlight, sunlamps, arc welding, or high-reflection surfaces such as snow or water can trigger the condition.

Clinical onset is typically delayed, with eye pain, a gritty or foreign-body sensation, tearing, redness, photophobia, and blurred vision developing hours after exposure. Symptoms often peak within 6 to 24 hours and may improve within 24 to 72 hours with appropriate care.

Pathophysiology involves UV radiation causing damage to corneal epithelial cells, producing punctate epithelial erosions. The injury is usually superficial and heals as the epithelium regenerates. More severe exposure can affect deeper corneal layers and prolong recovery.

Diagnosis is clinical, supported by history of UV exposure and examination. Fluorescein staining reveals punctate corneal staining. Slit-lamp examination helps assess severity and rule out other ocular injuries.

Treatment is primarily supportive. Patients should rest the eye and avoid rubbing. Use lubricating or preservative-free artificial tears; topical antibiotics may be used to prevent secondary infection. Short-term topical cycloplegics or oral analgesics may relieve pain. Topical anesthetics should not be used routinely. Most people recover within 1 to 3 days.

Prevention relies on proper eye protection: sunglasses that block 100% of UV-A and UV-B, or prescription protective eyewear when exposed to welding, sunlamps, or high-reflection environments. Education and prompt treatment reduce discomfort and complications.