Why is there myopia and astigmatism?

Abstract: the reason for astigmatism is that the refractive rate of each meridian of the cornea is inconsistent due to the uneven thickness of the cornea or the uneven curvature of the cornea, so that the light passing through these meridian cannot focus on the same focus. In this way, light cannot accurately focus on the retina to form a clear image, which is called astigmatism.

myopia has been very distressed, but myopia has “encountered” astigmatism, which makes people crazy! Many people have such questions in their minds: Why are my eyes astigmatism?

  1. What is astigmatism?

astigmatism is a kind of ametropia. Because the refractive power of the eye is different on different meridians, the parallel light cannot form a focus after passing through the eye refractive system. This refractive state is called astigmatism.

human eyes are not perfect. The cornea of some people is curved in a certain angle area, while others are flat. The reason for astigmatism caused by

and

is that the refractive rate of each meridian of the cornea is inconsistent due to these uneven thickness or uneven curvature of the cornea, so that the light passing through these meridian cannot focus on the same focus. In this way, light cannot accurately focus on the retina to form a clear image, which is called astigmatism.

  2. What kind of astigmatism do you belong to? There are two kinds of astigmatism, one is regular astigmatism and the other is irregular astigmatism.

A. regular astigmatism

regular astigmatism is mostly caused by congenital abnormal changes of cornea. There are also some acquired astigmatism, such as long eyelids, needle eyes or millet swelling, and poor eye posture for a long time (such as often squinting, rubbing eyes, lying reading, etc.), so that the eyelid pressing the cornea will also change the corneal radian, produce astigmatism and increase the degree of astigmatism.

in addition, some ophthalmic operations, such as cataract and corneal surgery, may also change the degree and axis of astigmatism.

B. irregular astigmatism

irregular astigmatism is mainly caused by uneven corneal refractive surface, such as corneal ulcer, scar, keratoconus, pterygium, etc.

  3. What factors can lead to astigmatism

A. often rub the eyes

professionals found in the survey that some people rub their eyes vigorously when they feel itchy due to eye discomfort and allergies, but they usually close their eyes when rubbing their eyes. At this time, the eyeball will move upward and the pressure will gather under the eyeball, Cause the radian under the cornea to change. Astigmatism occurs when the corneal radian is uneven.

B. wear inferior glasses

generally speaking, inferior glasses are produced by underground factories without certificates, with simple equipment and low cost, so the price is particularly low. In terms of lens materials, the resin matrix of inferior glasses is impure, which can cause visual deformation or dizziness. Large dispersion effect, easy to cause visual fatigue. In addition, it cannot prevent ultraviolet rays or can only prevent a small amount of ultraviolet rays.

  4. How can astigmatism patients protect their eyes? Avoid

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. Blinking often can reduce the time of eye exposure to the air and avoid the evaporation of tears.

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should not blow the air conditioner for too long to avoid airflow on the seat, and tea should be placed near the seat to increase the surrounding humidity.

eat more fruits, especially citrus fruits. You should also eat more green vegetables, grain, fish and eggs. Drinking plenty of water can also help reduce dry eyes.

keep good living habits, get enough sleep and don’t stay up late.

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avoid operating the computer continuously for a long time and pay attention to rest in the middle. Usually, operate continuously for 1 hour and rest for 5 ~ 10 minutes. At rest, you can look far away or do eye exercises.

keep good working posture. Maintain the most appropriate posture, make your eyes look flat or look down slightly on the fluorescent screen, which can relax the neck muscles and minimize the area of your eyes exposed to the air.