friends wearing contact lenses will find a problem, that is, after using contact lenses for a period of time, they always feel that there is sediment on them, which can not be washed off. At the same time, the lenses are not as soft as before, and there is even a hairy feeling on the edge. After they are brought into the eyes, they feel uncomfortable and dry more frequently than before, It’ll be better to take it off and rinse it. Some people say that if this happens, they must stop wearing and throw away this pair of glasses, but it will only take half a year next year or one month in the season. It’s a pity to throw them away, but they are worried about this & ldquo; Sediment & rdquo; Hurt your eyes, even feel pain, dryness, tears, unable to see clearly, and & ldquo; Blind & rdquo;, What are these sediments? Can they cause blindness? Next, let’s have a look with you.
3. Biofilm
biofilm is an rejection reaction of eye to contact lens. When wearing contact lenses, the mechanical stimulation of lenses and the stimulation of dry eyes increase the mucus of conjunctival goblet cells, and a large amount of mucus is adsorbed on the surface of lenses to form a transparent biofilm. The thinner biofilm is easy to fall off after rubbing, but it is relatively difficult to remove because the biofilm is thickened due to insufficient long-term wearing or cleaning.
4. Others: inorganic salts, fungi, rust spots, drug components, nursing fluid components, abnormalities of corresponding components in tears, lens surface pollution, etc.
note that visual acuity will fluctuate, but it does not constitute an inevitable condition for blindness, because timely treatment can repair the eyes, but repeated stimulation should not be allowed. Contact lenses can change the curvature of the corneal surface, but this & ldquo; Change & rdquo; It is reversible. Generally speaking, the outer cornea can be restored after stopping wearing for one week.
in addition, some people think that the contact lenses are blurred, and it is also good to shed tears without eye drops & ldquo; Flushing & rdquo; However, this is wrong and may be temporarily relieved, but when the tears evaporate, the residues of inorganic salts and proteins in the tears will cause more problems.
how harmful is wearing contact lenses?
concerns come again, because we often hear some statements about the harm of contact lenses to blablabla, what will cause corneal wear, vision loss, serious eye diseases and so on. That many girls are even worried about wearing contact lenses .
are contact lenses really that scary?
no, many people think that wearing contact lenses is harmful. In fact, it is not it that is the culprit, but these details you don’t care about & DARR& darr;& darr;
· Hands and tweezers are not clean when wearing, resulting in bacterial infection
& middot; Improper care leads to protein, lipid and collagen adhering to the contact lens surface to breed bacteria, resulting in further infection
& middot; Wearing it for too long will paralyze the nerve endings, resulting in decreased corneal perception
& middot; Wear for a long time, resulting in corneal hypoxia, edema, corneal neovascularization, dry eye, visual fatigue, etc.
& middot; Wearing “three noes” products that do not meet the national quality standards, or contact lenses that are inconsistent with their eyeballs and vision, may wear the cornea, cause corneal inflammation and ulcer, and cause irreversible decline in Vision & hellip& hellip;
the conclusion is: if you wear regular and suitable contact lenses, do a good job in cleaning and avoid wearing them for a long time, there is no big problem in wearing contact lenses.
How to choose contact lenses?
so how to choose suitable contact lenses? As far as I know, many girls buy it when they see that others say it’s good. They think it’s ok as long as the degree is right. They haven’t considered whether it’s suitable for them at all.
in fact, contact lenses, like frame glasses, need to go to an optical shop or hospital with a professional optometrist for optometry and other evaluation and examination. This is not only responsible for your eyes, but also to avoid wasting the contact lenses you buy because they are not suitable for you.
You can buy less data. In addition, you must know less detours. two hundred and twenty-two thousand three hundred and thirty-three trillion and one hundred and eleven million four hundred and forty-four thousand five hundred and fifty-five ▶ Base arc
this is the most relevant data about whether the glasses are suitable for you. The so-called base arc is simply the curve radian of the glasses. If it is not in line with your cornea, it is easy to lack oxygen when it is tight, slip when it is loose, and may also affect your vision.
It’s like wearing a pair of insteps or loose shoes. In short, it’s uncomfortable.
so how to choose?
this is closely related to the inspection mentioned above. The data after inspection can calculate their own suitable base arc. However, there may not be one that fully matches you on the market, so it’s OK to choose one that is larger than it but no more than 0.2mm. bc is generally used on the package.
▶ Diameter
diameter, as the name suggests, is the diameter of the lens. If the base arc is like the height of the instep of a shoe, the diameter is equivalent to the length of the shoe. It’s uncomfortable to wear large or small.
therefore, the diameter and base arc are very important for the selection of contact lenses. Generally speaking, it is the most comfortable with a difference of 0.2mm.
▶ Water content
all know that contact lenses are easy to dry after wearing for a long time, so many people want to choose moist ones, which depends on the water content.
however, it should be noted that high water content does not mean that you do not dry. On the contrary, because it needs more water, you use your tears to maintain balance, which will only make your eyes drier.
but if the water content is high, the oxygen permeability is good and it is more comfortable to wear, so how to choose?
It is suggested that you can choose the one with high water content every day, because it can’t wait for it to start absorbing your tears; However, for a long time, such as semi annual throwing and annual throwing, we should choose the one with low water content.
generally, those with water content less than 38% are low water content, and those with water content greater than 60% are high water content.
▶ The center thickness is
, and the center thickness of contact lenses will also affect the comfort. Generally, less than 0.04mm is ultra-thin, but it is a little uncomfortable to wear more than 0.1mm.
the thinner the center thickness, the better the oxygen permeability and more comfortable to wear. However, if it is too thin, it is not good and easy to be damaged.
if the eyes are easy ▶ For babies with dry eyes, I suggest you wear thicker ones instead, because thicker ones will have higher water content.
▶ Oxygen permeability
has been mentioned several times before, so what is it?
we all know how important oxygen is. It is also essential for the cornea. Whether you can keep healthy depends on it.
whether the oxygen permeability is high or not is related to all aspects of contact lenses. For example, as mentioned earlier, water content and high oxygen permeability are naturally good, and the center thickness also has an impact.
▶ The material of contact lenses
and the material of contact lenses also have a great impact on the oxygen permeability.
now the contact lenses are basically two kinds of materials: hydrogel and silicone hydrogel. If you wear glasses often, you know that silicon hydrogel is more expensive, and the fact is that its oxygen permeability is better.
not only is the oxygen permeation rate, but also the silicone hydrogel contact lenses are less prone to water shortages and are more comfortable to wear. So more and more contact lenses are now used in silicone hydrogels.
daily, monthly, semi annual and annual?
these are the most common ones on the market. Which one should I buy?
▶ & amp; Recommended index for annual sales of
: ★★☆
applicable