Photokeratitis and the risk of blindness due to snow exposure

03/01/2024

With the arrival of the winter season, enjoying the snow can pose a risk to ocular health. Photokeratitis is a painful condition that can be caused by excessive exposure to ultraviolet (UV) radiation reflected by the snow. While it typically involves only temporary discomfort, it carries a real risk of blindness if not addressed properly.

Photokeratitis is essentially a burn on the cornea, the transparent tissue at the front of the eye. Snow can reflect up to 80% of the sun's UV radiation, meaning that eyes can be exposed to dangerous levels of radiation even on cloudy days. When in a snowy and sunny environment, UV rays can damage the cornea within minutes, leading to snow blindness.

Symptoms of snow blindness include red eyes, a gritty sensation in the eyes, excessive tearing, and light sensitivity. While these symptoms are generally temporary, repeated and unprotected exposure can have long-term consequences. The most severe risk is the possibility of developing snow blindness, a condition where cumulative damage to the cornea results in permanent vision loss.

Prevention is key when it comes to protecting our eyes from the risk of photokeratitis and snow blindness. Wearing sunglasses with adequate UV protection is essential, as they not only reduce the amount of UV radiation reaching the eyes but also prevent glare caused by light reflected off the snow. Ensuring that sunglasses or snow goggles fully cover the eyes and sides helps maximize protection.

If you suspect you have snow blindness after exposure to the snow, it is important to take steps to relieve symptoms and protect your eyes. Some recommendations you can follow include:

• Eye Rest: Reduce exposure to bright light and avoid direct sunlight.
• Frequent Blinking: Blink more often to help lubricate the eye surface.
• Artificial Tears: Use preservative-free artificial tears to keep the eyes lubricated.
• Avoid Eye Rubbing: Refrain from rubbing the eyes, as this can worsen irritation.
• Cold Compresses: Apply cold compresses over closed eyes to alleviate irritation.
• Analgesic Medications: Take over-the-counter pain relievers as directed to ease pain.
• Sunglasses: Wear UV-protective sunglasses to shield your eyes from sunlight.

Although these measures may provide temporary relief, seeking medical attention is crucial. If symptoms persist or worsen, it is recommended to consult an ophthalmologist or seek emergency care. The healthcare professional can assess the severity of the injury and provide appropriate treatment.

Dr. Anton Barraquer, Ophthalmologist at the Barraquer Ophthalmology Centre