Editor’s Note: I have seen welders holding protective masks or wearing protective goggles welding on the road. Have you ever thought that welders should not look at it. This must be very destructive light. Will my eyes be blind if I look at it carelessly?
Dr. Clove asked a professional ophthalmologist to tell you!
Ultraviolet rays are the culprit.
Welding is actually an intense and continuous discharge process. Photons of different wavelengths are excited at different temperatures to form an arc. Therefore, this arc is not only visible light to human eyes, but mainly contains three different wavelengths of light sources-infrared, visible and ultraviolet.
Among them, a large number of ultraviolet rays invisible to the naked eye are the invisible killers that damage the cells on the eye surface.
The [black eye] part of the eye is actually covered by a transparent layer of corneal tissue, while the [white eye] is wrapped by a layer of conjunctival tissue with blood vessels. The cornea and conjunctiva form the surface tissue of the eye.
Ultraviolet rays can be absorbed in large quantities by epithelial cells in the surface tissue of the eye, It causes edema and necrosis, causing extensive epithelial cell defects and inflammation. Within a few hours, the patient’s symptoms can gradually develop from the initial foreign body sensation, jealousy and tears in the eyes to extreme stabbing pain, fear of light, burning sensation, and even inability to open his eyes and sleep. It is often not until this time that the patient hurries to the hospital in the dim light of night.
Why is it so painful? Because the surface of the eyeball is distributed with a large number of nerve fiber endings, especially the cornea, which is the part of the black eye, making it extremely sensitive to external stimuli. Why can’t the eyes hold sand? This is the reason.
[Electro-optic ophthalmia] Another name is [snow blindness]
Because of the eye injury caused by welding without wearing protective glasses, the professional diagnosis is called [electro-optic ophthalmia].
But it is not exposure to ultraviolet rays that causes electro-optic ophthalmia, Otherwise, we will all hide from the sun. Compared with welding, The intensity of ultraviolet rays in the natural environment is much lower. In fact, only long-term and large-dose exposure to ultraviolet rays can cause such damage. Therefore, as long as there is no close and long-term gaze, passers-by passing by the welding will not be affected by it. Therefore, walking in the sun should not be too worried.
However, if you are exposed to high-reflection ultraviolet rays such as snow and water for a long time, there is also a risk of electro-optic ophthalmia. Therefore, it has an alias called “snow blindness”. This is also why alpine athletes wear goggles.
Do you blindness when you see welding?
[Emergency, eye pain, welding.] Night shift nurses often hear such words on the phone. Because there are so many welders who do not pay attention to self-protection in welding, our experienced nurses can diagnose: electro-optic ophthalmia, welding without protective glasses.
Accompanied by severe pain, many patients are worried. The first question to see a doctor is: “Am I blind?” ]
I usually answer: [No, blindness is only possible if you are infected or your corneal healing ability is too poor.]
Generally speaking, the cornea and conjunctiva regeneration repair ability is very strong, the vast majority of patients can be cured within a few days. Before healing, due to the eyes can not open, tears and eye inflammatory reaction and other factors, can appear short blurred vision, need not be too nervous.
At this time, accompanying family members often asked me: “when he was welding, I was nearby. Why am I okay?” ]
Because ultraviolet rays only travel in a straight line and are easily weakened in the process of propagation. The following conditions must be met: high intensity, close distance, long time and exact fixation angle, which will lead to damage to ocular surface cells.
Therefore, when we walk in the street and see someone welding on the roadside, as long as we don’t stare at it, our eyes will be fine.
In addition, ultraviolet rays of different wavelengths can be absorbed by different tissues of the eye. The incidence of pterygium, cataract and other diseases in high altitude areas is relatively high, which is closely related to relatively strong ultraviolet rays. Although the development of these diseases is slow, they may also significantly affect vision in the future.
Can snow blindness be cured?
Sometimes the patient is too miserable, And can’t even open your eyes and cooperate with the examination, Doctors may drop some special topical anesthetic for eyes. For pain caused by electro-optic ophthalmia, It can be said that there is an immediate [miraculous effect], but it does not last long. Some studies have proved that it can delay the healing of eye surface epithelium, so it must not rely on topical anesthetics. Oral painkillers are a good choice, as long as there are no contraindications, you can take them safely, but the analgesic effect may be relatively slow.
In addition, eye drops or gel that promote epithelial growth can be used, Accelerate healing. Since most of the patients are frontline workers, The working environment may be relatively poor, preventive point with antibiotic eye drops, and emphasize to avoid eye contact with external germs, do not rinse or rub the eyes, it is very necessary. Damaged cornea’s ability to resist germs decreases, once infected, a common keratitis develops into infectious corneal ulcer, the consequences are unimaginable.
Contrary to those above who are particularly nervous, Other patients feel pain is not so obvious, don’t come to the hospital. You know, sometimes ultraviolet may not be the only killer. In the process of welding, there may also be infrared caused by eye thermal burns, foreign bodies into the eye and other situations. Therefore, do not take it lightly, must go to the hospital in time.
Prevention is of paramount importance
I can’t open my eyes. I need several family members to help me to get to the hospital. I still have to worry about whether I will be blind… Even if it’s not a serious illness, no one wants to experience such a painful night, does it?
Therefore, whether you are a worker who burns or watches others, a warm-hearted neighbor who helps pet shops repair ultraviolet lamps, or a hiker who crosses plateaus, snowy mountains and glaciers-as long as you may be exposed to a large amount of ultraviolet radiation, please, wear, protect, protect and mirror. This is the most sincere education of an ophthalmologist.
Responsible Editor: Fei Fei