What Is Snow Blindness?

Can suffer from "snow blindness" on cloudy days

Snow blindness

Snow blindness is a symptom of temporary blindness caused by strong light stimulation of the retina of the eye. The reflectivity of snow to daylight is extremely high, which can reach nearly 95%. Looking directly at the snow is just like looking at the sun. Because this symptom often occurs on mountain climbers, snow and polar explorers, it is called snow blindness. Similar symptoms can occur in welders who do not wear protective devices.

Introduction to Snow Blindness

Can suffer from "snow blindness" on cloudy days It occurs on mountain, snow, and polar explorers and is therefore called snow blindness. Similar symptoms can occur in welders who do not wear protective devices.

The mountaineers and scientific expedition members who are active in the snow-covered areas of high mountains and glaciers pay little attention, forget to wear sunglasses, and often sting their eyes with snow reflections, and even temporarily lose their sight. This phenomenon is called "snow blindness" in medicine. After a few days of rest, vision generally recovers on its own. People who have experienced snow blindness will become snow blind again if they don't pay attention. Once again, the symptoms of snow blindness will be more serious, so don't be careless. Repeated snow blindness gradually weakens people's eyesight, causes long-term eye diseases, and even blindness in severe cases

Causes of Snow Blindness

"Walking in the snow is a very dangerous thing. It can easily cause people to suffer from snow blindness. They can't see the route and lose their way of travel. So many people think that it is caused by the sunlight reflected from the snow. Actually, otherwise, the strong light will only cause damage to the eyes, and snow blindness is not caused by it. So wearing sunglasses will also cause snow blindness.

According to a study by an authoritative department in the United States, the main cause of snow blindness is that there is nothing in the snow. Scientists have verified that human eyes are always tirelessly exploring the world around them, from one point to another. If you search for a long time without finding any point, it will become blind due to tension.

The US Army has found a way to deal with snow blindness. They sent pioneers to put darker flags on the march in advance. In this way, in the white snow, there are eye-catching signs, and people's search eyes have settled, so that the long-term blank will not cause blindness due to optic nerve tension. " In fact, this is a very rumor that is widely spread in the Reader's Digest .

Causes of snow blindness

Who is the culprit for snow blindness? It turns out that snow is a very high reflectivity of sunlight. The so-called reflectance refers to the ability of the surface of any object to reflect sunlight. This reflection ability is usually expressed as a percentage. For example, the reflectivity of an object is 45%, which means that 45% of the solar radiation received on the surface of the object is reflected. Snow reflection

High snow reflectivity can cause snow blindness when viewed for a long time The rate is extremely high, and the reflectivity of the pure fresh snow surface can be as high as 95%. In other words, 95% of solar radiation is reflected off the snow surface again. At this time, the snow surface is almost as bright as the sun. How can the retina of the naked eye withstand such strong light stimulation?

On the vast expanse of snow in Antarctica, the snow surface in some places is slightly depressed, like the concave surface of a searchlight. In such places, white light may appear. The snow surface with white light is of course more concentrated and stronger than the sunlight reflected by ordinary snow surface. In general, the snow surface does not directly reflect sunlight into the human eye like a mirror, but stimulates the eyes through the snow surface's scattering. When the human eye is stimulated by this scattered light for a long time, it can also get snow blindness. Therefore, even on cloudy days, people who haven't worn sunglasses for a long time on the snow may temporarily lose their eyes.

Preventing Snow Blindness

The cause of snow blindness is because both eyes are exposed to the snow, and the cornea without the protection of sunglasses is easily injured, because the reflection of the snow is very strong regardless of whether it is exposed to the sun or not. Within a short time can cause severe snow blindness. Symptoms of snow blindness are very painful eyes. The eyes feel like they are full of wind and sand, the eyes are red, they often shed tears, they are very sensitive to light, and it is difficult to open their eyes.

To prevent snow blindness, you can wear UV-resistant sunglasses, choose polycarbonate or CR39 lenses, or frog-style full-faced gray glasses, and supplement vitamin A, vitamin B group, vitamin C, and vitamin E.

If you have symptoms of snow blindness, you can cover your eyes with a blindfold and clean gauze. Do not force your eyes and seek medical attention as soon as possible. Symptoms of snow blindness generally recover within 24 hours to three days.

Snow Blindness Treatment

Patients with snow blindness usually have both eyes at the same time.

Frog-style full-faced gray glasses Foreign body sensation in the eyes. If snow blindness occurs, the following first aid measures can be implemented:

1. Wash your eyes with cold water or eye drops. Secondly, cover your eyes with an eye patch or similar (clean handkerchief, gauze, etc.). Try to rest and avoid using your eyes unreasonably. Seek medical attention if necessary. Generally, the symptoms of snow blindness can be recovered within 24 hours to three days, and the more severe symptoms usually take 5 to 7 days to resolve.

2.Another Tibetan exclusive recipe: use a mosquito head to make a soup. After the soup is wet with a towel, apply it to the eyes and repeat 3'4 times.

Treatments for snow blindness include pain relief and preventing re-injury. Contact lenses must be removed and the eyes must be protected from strong light. Remind snow blind people not to rub their eyes and try to rest. In order to avoid the movement of the eyelids disturbing the eyes, it may be better to cover the eyes with a disinfected cloth and pads, and check the sensitivity of the eyes to light every half day. When the eyes are no longer extremely afraid of light, you can remove the dressing, but you should always wear protective sunglasses.

Once you have snow blindness, you can use fresh human milk or fresh milk drops, 5-6 drops each time, every 3-5 minutes. The milk used must be boiled and allowed to cool.