Overview

Snow blindness, medically known as photokeratitis, is a painful eye condition caused by overexposure to ultraviolet (UV) rays reflected off snow and ice. It is essentially a sunburn of the cornea, the clear front surface of the eye. This condition is common among skiers, mountaineers, and individuals spending extended periods in snowy environments without proper eye protection. Snow blindness can cause temporary vision loss and significant discomfort, but with timely care, it usually resolves within a few days without long-term complications.

Causes

Snow blindness occurs when the eyes are exposed to high levels of UV radiation. The primary causes include:

• Reflected UV Rays: Snow reflects up to 80% of UV light, greatly increasing exposure compared to other environments.
• Direct Sunlight at High Altitudes: UV radiation intensifies at higher elevations, increasing the risk during mountain activities.
• Lack of Eye Protection: Not wearing sunglasses or goggles with UV protection in snowy areas leads to greater risk.
• Artificial UV Sources: Tanning beds or welding torches can also cause similar corneal burns, known as flash burns.
• Prolonged Exposure: Even cloudy days in snowy regions can contribute to UV damage due to diffuse reflection.

Symptoms

Symptoms of snow blindness typically develop several hours after UV exposure and can include:

• Eye Pain or Burning: A sharp, painful sensation in the eyes is the most common symptom.
• Redness: The eyes appear red and irritated due to inflammation of the cornea.
• Watery Eyes: Excessive tearing is a natural protective response of the eyes.
• Blurred Vision: Temporary difficulty seeing clearly, often accompanied by sensitivity to light.
• Gritty Sensation: Feeling like sand or grit is stuck in the eyes.
• Swollen Eyelids: Mild swelling of the eyelids can occur due to irritation.
• Headache: Eye strain and discomfort may lead to headaches.
• Temporary Vision Loss: In severe cases, people may experience temporary loss of vision, which typically resolves within 24-48 hours.

Diagnosis

Diagnosis of snow blindness is based primarily on clinical history and eye examination:

• Medical History: Recent exposure to snow, high altitudes, or UV sources without proper eye protection is a key clue.
• Symptoms Assessment: Description of eye pain, light sensitivity, and vision changes helps with diagnosis.
• Slit-Lamp Examination: An ophthalmologist may use a slit lamp to examine the cornea and identify superficial damage or corneal abrasions.
• Fluorescein Staining: Special dye can be used to highlight corneal damage under blue light.

Treatment

Treatment for snow blindness focuses on relieving symptoms and promoting healing of the cornea. Fortunately, the condition is usually self-limiting and resolves within a few days.

Self-Care Measures

• Resting the Eyes: Avoid further UV exposure and stay in a darkened environment until symptoms improve.
• Cold Compresses: Applying a cool, damp cloth can help reduce discomfort and swelling.
• Artificial Tears: Lubricating eye drops soothe irritation and dryness.
• Avoid Rubbing Eyes: Rubbing can worsen corneal irritation and slow healing.

Medical Treatment

• Pain Relief: Oral painkillers like ibuprofen can help manage pain and inflammation.
• Antibiotic Eye Drops: Sometimes prescribed to prevent secondary infection, especially in cases with corneal abrasions.
• Eye Patching: Rarely used nowadays, but in some cases, patching may help reduce eye movement and irritation.
• Follow-Up Care: Medical follow-up is advised if symptoms persist beyond 48 hours or worsen.

Prognosis

The prognosis for snow blindness is excellent in most cases. Symptoms typically resolve within 24 to 72 hours without any permanent damage to the eyes. With proper rest and supportive care, full vision usually returns quickly. Severe cases, though rare, may take longer to heal but still have a favorable outcome.

Preventing snow blindness is straightforward—using high-quality sunglasses or snow goggles with 100% UV protection, wearing a wide-brimmed hat, and limiting exposure during peak sunlight hours. With preventive measures and early treatment, snow blindness can be effectively avoided and managed.