Can children wearing framed glasses prevent myopia from getting worse?

Among the myopia prevention and control technologies for children and adolescents, "specially designed frame glasses" are one of them. As the name suggests, this type of glasses is specially designed to control the progression of myopia, and is not an ordinary frame glasses.

What is so special about it? Why can it prevent and control myopia? Is the effect significant? This article will discuss these topics. As usual, Dr. Jingcai promises that this is pure popular science, no deception, no selling, please feel free to read.

Ordinary myopia frame glasses have single-focus concave lenses. They can correct myopia. However, when looking at close objects, only the center of the retina can be focused accurately, and the peripheral parts will form "hyperopic defocus", that is, focusing behind the retina, as shown in the following figure (green dotted line):

So, what is so special about specially designed frame glasses? They all focus on the lens design, and there is no essential difference in the frame.

The first category is multi-point myopia defocus lens design.

This type of lens design occupies the vast majority of specially designed frame glasses. Its theoretical basis is the "peripheral defocus theory" of myopia: that is, by creating myopic defocus in the peripheral part of the retina through specific means, the progression of myopia can be effectively inhibited. Taking the "xqukong" lens as an example, its central area can correct children's myopia and ensure clear focus in the central area of ​​the retina; while the peripheral area of ​​the lens has 1021 aspherical micro lenses distributed in 11 rings, as shown below:

It is precisely with this design that myopic defocusing can be formed in the peripheral area of ​​the child's retina, that is, focusing in front of the retina. As shown in the following figure (green dotted line):

According to clinical research data of "xqukong", wearing the lenses for 12 hours or more a day can slow down the progression of myopia in children by 67% compared with ordinary myopia lenses; after one year of wearing, 90% of children wearing the lenses have eye growth similar to or slower than that of non-myopic children, and two-thirds of them do not need to replace the lenses after the first year.

The second category is lenses designed using the "retinal contrast theory".

Genetic studies have shown that children with mutations in the myopia-related gene locus MYP1 will have abnormally increased retinal contrast signals, which may lead to high myopia. This theory is highly professional, so we won’t go into it in depth.

According to this theory, if the contrast of the signal received by the retina can be reduced through lens design, the progression of myopia should be controlled.

Take the "DOT" lens as an example, it is designed in this way. The central area of ​​the lens corrects the child's myopia and forms a clear image on the retina, while the periphery of the lens looks like "a layer of fog", which is actually thousands of light diffusion points that gently diffuse the light to reduce the contrast.

According to the first year clinical research data of "Control X Point", 65% of children had no obvious worsening of myopia in the first year of wearing;

Two years of clinical trial data show that full-day wearing can delay myopia progression by an average of 59%; 41% of children have no significant worsening of myopia; it is especially effective for children aged 6 to 7 years old whose myopia is rapidly developing.

Now you know that the lenses of frame glasses that can prevent and control myopia are specially designed, not ordinary single-focus concave lenses. The theoretical basis and ideas of the design are mainly divided into two categories: "peripheral defocus theory" and "retinal contrast theory". Most of the products on the market are products supported by the "peripheral defocus theory".

In addition, there are products based on different theories such as accommodation theory, competitive defocus, phase difference theory, etc., which we will introduce in the future.

If you find this article helpful, you are welcome to forward it to other parents who may also need it. Thank you.

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About Dr. Jingcai: The creators of Dr. Jingcai's popular science content all have a professional background in ophthalmology, a master's degree or above, and are former ophthalmologists. For some popular science content with a higher degree of professionalism, we will also invite working ophthalmologists and optometry experts to review and check it, striving to be responsible for the accuracy of the content and avoid misleading readers.