However, in our country, it has been recognized as three types of medical devices by the Food and Drug Administration. Because it is in direct contact with the human body, the management standard is the same as that of heart valves.
Therefore, its purchase, wearing, nursing and strict requirements can be imagined. In fact, there are 1, 2, 3 common misunderstandings in contact lenses, which should also be known.
Myth 1: Soft mirror is definitely better than hard mirror.
Do you know contact lenses? Soft? 、? Work hard? The difference?
Soft lenses are generally made of hydrophilic materials such as hydrogels and hydrated polymers, so the lenses are soft and elastic. Hard mirror is hard and hydrophobic, so it is not as obedient as soft mirror. When you wear it, the lens is relatively fluid and has a heavy foreign body feeling.
Many people draw a conclusion according to the comfort of lenses: soft lenses are good, but hard lenses are not. In fact, this is a prejudice. In the eyes of ophthalmologists, hard glasses play a very important role.
For example, hard contact lenses are made of materials with high oxygen permeability, which is very beneficial to the health of cornea. Moreover, compared with soft lens contact lenses with high oxygen permeability, hard lenses can also solve the astigmatism problem at the same time, and the visual quality is better.
Soft and hard lenses have different effects, but it is suggested that people with astigmatism, high myopia and high visual quality, as well as young people, can consider wearing hard contact lenses with high oxygen permeability.
Myth 2: Wear cosmetic contact lenses for a long time.
If you want to make your eyes bigger and better looking, wear a pair of beauty contact lenses. Many young girls have this idea.
Cosmetic contact lens, from a professional point of view, is a special kind of colored contact lens (with pigment in the lens). It can decorate the eyes, but it also has some disadvantages:
? Thicker than ordinary contact lenses.
? Pigments in lenses may affect the surface of the eyes.
? Considering the cost factor, the materials of cosmetic contact lenses are mostly not high oxygen permeability materials, so the consequences of corneal hypoxia can be more serious.
In particular, cosmetic contact lenses are more harmful to the eyes if they are worn irregularly. In order to cut costs, individual manufacturers will put pigments directly on the surface of glasses, which will directly contact the cornea when wearing, and will have toxic reactions to the cornea for a long time. Dr Zhu Jianfeng, deputy director of the Optometry Center of Shanghai Eye Disease Prevention and Control Center, once encountered a serious case of infection caused by wearing this cosmetic contact lens.
Therefore, cosmetic contact lenses are not recommended to be worn for a long time. You can wear it occasionally at parties and special occasions, but never all the time.
Myth 3: Feel free to wear OK glasses.
OK glasses, which are very popular now, can help teenagers control myopia at night, and adults don't need to wear glasses during the day. In fact, it is also a hard contact lens.
However, such a kind of contact lens with special function requires very high skills and experience in fitting: it must be fitted by regular medical institutions and experienced doctors. Without professional guarantee, it is very likely that there will be problems when trying on OK lenses.
In addition, after fitting the OK mirror, it is necessary to make regular follow-up visits and conduct systematic inspection.
For wearing such medical devices, Dr. Zhu Jianfeng suggested that they should be worn in functional occasions and when there is a need for life and work, and should not be worn in unnecessary occasions such as home and daily work. Try not to wear contact lenses for a long time, and pay attention to the indications: frequent eye inflammation, dry eye, corneal injury or eye lesions are not suitable for wearing contact lenses. If you wear contact lenses for a long time, you must have your eyes examined.
Companies and enterprises that regularly sell contact lenses should have permission to sell three types of medical devices. If there is no license, it means that the other party has no sales qualification, so pay attention when buying. The simplest way to buy it is to try to go to large well-known glasses chain institutions, eye or optometry centers in hospitals, and some contact lens monopoly institutions.