Reporter Jia Xiaoying Correspondent Nadi Although the summer sun brings bright weather and splendid scenery, it poses a potential threat to our eyes. Zhao Long, an ophthalmologist at Hulunbuir People's Hospital, reminded the general public that ultraviolet rays are invisible killers in sunlight, and the damage to the eyes is long-term and cumulative. During this season, it is especially important to pay attention to the health protection of the eyes.
What are the specific damage of ultraviolet rays to the eyes?
Zhao Long: 1. Ultraviolet rays can induce skin carcinogenesis of the eyelids, such as basal cell carcinoma, squamous cell carcinoma and malignant melanoma.
2. Long-term light radiation at the limbus can cause local epithelial cell damage, corneal conjunctival barrier destruction, and excessive proliferation of conjunctival tissue to the cornea.
3. Light damage to the lens and the resulting increase in cataracts. Due to the decrease in the ozone layer and the increase in ultraviolet radiation, there is a higher incidence of cataracts.
4. Because the cells of the retinal pigment epithelium contain a large number of photosensitizers, they can constantly engulf light, and are often exposed to ultraviolet rays, oxidative stress may occur, resulting in apoptosis of photoreceptor cells and retinal pigment epithelial cells, and eventually lead to pathological damage such as age-related macular degeneration.
What are the strongest times of day in summer, and which types of UV rays (UVA, UVB, UVC) are most harmful to the eyes?
Zhao Long: According to the absorption characteristics and biological effects of different wavelengths of eye tissue, that is, the shorter the wavelength, the greater the energy of a single photon, and the weaker the ability to penetrate eye tissue, so it is divided into UV-C (
Because the UV-C radiation in sunlight can be completely absorbed by the ozone and moisture in the atmosphere, UV-A, UV-B are the main components of sunlight, and the ozone layer is the most important advection barrier of UV-B radiation.
The degree of damage to the human eye from ultraviolet rays depends not only on the wavelength of ultraviolet rays, but also on the duration and intensity of radiation. The impact of ultraviolet rays reaching the surface is affected by the following factors: (1) Season: In summer (May to September), the intensity of ultraviolet rays will increase by at least 10%-20% depending on the region because of the closer distance from the sun. (2) Latitude: The incidence of cataract increases with the decrease of latitude in the world, and the intensity of ultraviolet rays is stronger the closer to the equator, and the age of cataract onset in tropical countries is usually 10 years earlier than that of temperate countries. (3) Time: The time close to noon (about 10:00 a.m. to 2:00 p.m.) is the time when the UV intensity is the strongest. (4) Altitude: For every 1,000 feet of altitude, the intensity of ultraviolet rays will increase by 5%, so the higher the altitude, the stronger the ultraviolet rays, and the damage of ultraviolet rays is cumulative.
What eye diseases can long-term exposure to UV rays cause?
Zhao Long: 1. Ultraviolet rays can induce skin carcinogenesis of the eyelids, such as basal cell carcinoma, squamous cell carcinoma and malignant melanoma.
2. Corneal and conjunctival diseases: Corneal damage caused by ultraviolet rays depends on the wavelength and intensity of ultraviolet rays. Natural light generally does not cause corneal damage, and can only occur in special environments such as snowy wilderness or under artificial UV light sources. Among them, the incidence of climatic guttate keratodegeneration (CDK) was higher among herders in Hulunbuir area, and the incidence rate was 21.6% in 2558 people in Animal Husbandry Siqi, including 21.7% in males and 21.6% in females.
3. Damage to the lens: The effect of ultraviolet rays on the lens is a long-term, chronic accumulation of oxidative damage process. Epidemiological studies have shown that the amount of UVB radiation in the environment is positively correlated with the incidence of cataracts in the population.
4. Retinopathy caused by ultraviolet rays: Because the cells of the retinal pigment epithelium contain a large number of photosensitizers, they can constantly engulf light, and are often exposed to ultraviolet rays, oxidative stress may occur, resulting in apoptosis of photoreceptor cells and retinal pigment epithelial cells, and eventually lead to pathological damage such as age-related macular degeneration (AMD).
How can members of the public protect their eyes from UV rays in their daily lives?
Zhao Long: Preventing UV damage to the eyes has become an important lesson that each of us must do all year round. In addition to avoiding going out during the time when the UV rays are at their strongest (about 10:00 a.m. to 2:00 p.m.), there are two more proactive ways to do so: (1) Wear a hat with a wide brim. Because a hat with a wide brim can block 30% of the sun. (2) Wear UV-blocking sunglasses, because UV-blocking sunglasses can absorb more than 90% of UV rays, so a good pair of sunglasses has become the key to protecting your eyes from UV rays.
How to choose the right sunglasses to effectively protect against UV rays?
Zhao Long: When buying sunglasses, you must buy them from a quality assurance glasses store, because sunglasses can block ultraviolet rays because there is a special coating on the lens, which can effectively block UVA and UVB through the lens and protect the eyes. Secondly, the choice of lens color is also crucial to the eye protection effect. Grey and brown lenses have the best eye protection effect, especially gray lenses have good light transmittance, which can best balance all color systems, and are the most natural, peaceful and warm tones. Try to avoid wearing blue and pink sunglasses, as blue lenses not only cannot block visible light in blue, indigo and violet, but also attract these harmful blue rays into your eyes. Of course, it is not recommended to use black lenses, because wearing glasses that are too dark will make the eyes in a darkroom environment, and the pupils of human eyes will automatically dilate in a dark environment, and long-term dilation of the pupils is easy to cause glaucoma and other diseases, and black has a covering effect on all colors. Thirdly, there are contact lenses on the market that protect against ultraviolet rays, but contact lenses can only protect the cornea, and ultraviolet rays can also cause damage to other parts of the eye, such as eyelids and whites. To truly protect your eyes from UV damage and effectively reduce the risk of cataracts and pterygium, the right way to do this is to wear contact lenses and choose high-quality sunglasses with wide brims to protect the entire eye and the skin around the eyes. Sunglasses are not exclusive to summer, nor are they for adults, but not for all situations. Some people like to wear sunglasses both indoors and outdoors, in fact, in the shade without sunlight, they should be taken off and let their eyes rest in natural light for a while, while healthy preschoolers, stereoscopic vision is not yet mature, so it is completely unsuitable for wearing sunglasses.
Doctor Profile:
Zhao Long is an ophthalmologist at Hulunbuir People's Hospital. He has been engaged in comprehensive ophthalmology clinical work for many years and has rich experience, and has expertise in the diagnosis and treatment of corneal diseases, glaucoma, cataracts and other ophthalmic diseases.
In 2015, he obtained a master's degree in ophthalmic medicine, and while completing clinical and teaching work, he actively carried out scientific research, independently presided over and completed a project, and published 2 articles in science and technology core and national journals and 3 provincial journals.
