Two, the United States FDA and National Medical Products Administration, China have stipulated that orthokeratology is the third kind of medical devices. The third kind of medical equipment is the medical equipment with the highest risk level. How can such a medical device with the highest risk level (orthokeratology) be used for general myopia in children?
1 First of all, the author also admitted that orthokeratology mirror was certified by FDA and National Medical Products Administration, China, so its legality was recognized. You can go to the website of China Food and Drug Administration and search for "Orthokeratology Mirror" in medical devices. There is a scope of application of related products, which clearly shows that myopia can be corrected.
2. Why should it be classified into the third category of medical devices? It is precisely because the country has strict requirements for this technology that no organization can do it. Is a strict medical behavior, must be in accordance with the relevant provisions of the state to obtain the third class medical device qualification certificate, and in a qualified optometry professional fitting institutions.
3. There is no age limit for the applicable population of orthokeratology. The main test rate is the children's own hands-on operation ability, which is generally required to be 8-40 years old.
Third, if you are not careful, the corneal plastic mirror will make the cornea inflamed, perforated and blind.
How to correctly understand the five hazards of orthokeratology mirror
Aiming at this problem, it is also the most concerned issue for all parents. China introduced this technology from 1998, and millions of people have received this treatment so far. In the first 2-3 years, due to the lack of medical management and standardized operation, the hospitals carrying out this technology did not know enough about orthokeratology to treat myopia, and the experience and technology of fitting were very limited. Consumers' compliance is poor, media advertisements and product propagandists exaggerate and mislead, and some unqualified companies and optical shops have also started to sell orthokeratology lenses as ordinary goods, which has formed a chaotic situation of mixed good and bad. The quality of orthokeratology lenses has not been strictly supervised by the relevant departments, which led to some serious bad orthokeratology lenses among the wearers in China in the first few years, which attracted the close attention of relevant media at home and abroad. Of course, this problem has a lot to do with the patient's improper operation and failure to review on time.
Therefore, many adverse reactions caused by wearing orthokeratology glasses on the Internet now occur at that stage rather than at the present stage. At present, orthokeratology has developed to the latest fourth-generation products, and there are few reports on serious adverse conditions when wearing orthokeratology in the media. Strict fitting by qualified optometrists+qualified lenses+qualified users (patients) = safe and effective.
Fourth, "lack of oxygen."
General "dry eye" was formed in 1-2 years. At present, the country stipulates that the DK value (oxygen permeability) of night lenses should be above 90, but now the oxygen permeability of orthokeratology lenses is above 100, even reaching 140.
The formation of dry eye is related to one's own physique and eye habits, rather than being completely formed after wearing plastic glasses. At the initial stage of fitting, children are usually examined for dry eye. If they have severe dry eye, they are not suitable for matching. Most of the nearsighted teenagers in China have symptoms of dry eye and conjunctivitis, but we didn't have a routine examination in this area before fitting glasses, so we didn't know about these problems. However, doctors may mention symptoms such as dry eyes after wearing glasses, so many parents think it is caused by wearing glasses, but it is not. Look at those children who don't wear plastic glasses, and there will still be such problems. In addition, parents should look at their children's usual eye consumption, especially in junior high school and high school. They have little rest time. They either attend classes at school or do their homework at home, or make up lessons in cram schools. A serious lack of sleep time and severe visual fatigue will invisibly increase the burden on the eyes and cause some eye diseases.
Fifth, the corneal center becomes thinner; The thinning of corneal center is one of the main reasons for keratoconus (commonly known as "exophthalmos").
Our normal central corneal thickness is about 0.565 mm Observing the patients who have been wearing it overnight for 7 years, it is found that the central corneal thickness is slightly thinner than 0.009mm after wearing it, but the difference is not statistically significant. In addition, at the initial stage of fitting, the patient's corneal thickness will be checked, and if there is keratoconus, it is not suitable for fitting.
6. Corneal curvature deformation (the center of the cornea is thinner and the periphery is relatively higher).
As most ophthalmologists know, our cornea is elastic. At the beginning of wearing glasses, the central tissue of cornea moves to the periphery due to pressure, and the thickness of epithelial cells becomes thinner and the width increases, thus improving the naked eye vision. However, the number, capacity and area of corneal epithelial cells are constant. The corneal parameters examined after wearing glasses are definitely different from those before wearing glasses. The cornea is reversible. Generally, after stopping using it for about one month, the shape of the cornea will return to its original shape, rather than the corneal deformation described by the author.