Many parents who take their children to the ophthalmology clinic are more worried when they hear "astigmatism" than when they hear about myopia or farsightedness. Everyone knows astigmatism, but they don't know what astigmatism is. So, what is astigmatism, why does astigmatism occur, and what happens if it does?
Today, Zhang Mengjia, an eye prevention physician from Yangpu District Eye Disease Prevention and Treatment Institute and Yangpu District Kongjiang Hospital, will take you to understand astigmatism and understand your astigmatism.
What is astigmatism?
Astigmatism refers to the image formed by the refraction of parallel light through the eyeball, which is not a focal point, but the smallest diffusion circle between two focal lines and focal lines at different positions in space, and this refractive state is astigmatism. Like myopia and farsightedness, it is a type of refractive error, but it can exist alone or in combination with myopia or farsightedness.
The main symptoms of astigmatism are blurred vision, vision loss, visual fatigue, and sometimes torticollis and headache.
Why does astigmatism occur?
Myopia and hyperopia are caused by the fact that the focal point formed by the parallel rays from the outside world does not fall on the retina after passing through the refractive system of the eye, while astigmatism is due to the difference in the refractive power of the refractive system (cornea, lens, etc.) in different directions.
Therefore, myopia and hyperopia are blurred things that see far and near, while astigmatism is more blurred in a certain direction of seeing things.
The occurrence of astigmatism is divided into congenital and acquired factors:
1. Congenital factors
When the fetus is in the mother's womb, it is not in a state of silence, but rolls around. If you roll well and roll evenly, the development of the cornea will be more symmetrical, and it will be like a watermelon, and if it is not rolled well and unevenly, the development of the cornea will be uneven, and it will be like a cantaloupe. In fact, most astigmatism is related to congenital factors, and children and adolescents with astigmatism in either parent have a higher rate of astigmatism than those without both parents.
2. Acquired factors
Long-term poor eye posture, such as frequent squinting, eye rubbing, lying on the side and playing with mobile phones, etc., may lead to corneal compression, changes in corneal curvature, and increased astigmatism. These factors not only affect astigmatism in children and adolescents, but also have a great impact on astigmatism in adults, because astigmatism changes in direction in addition to changes in degree. In addition, diseases, trauma, surgery, etc., can cause changes in the curvature of the cornea and lens, causing astigmatism.
What should I do if I have astigmatism?
First of all, it is important to realize that astigmatism is as irreversible as myopia and cannot be cured. The essence of astigmatism is a kind of refractive error like myopia, and on the basis of this principle, the treatment of myopia is also applicable to astigmatism.
1. Glasses: Astigmatism causes symptoms such as vision loss or visual fatigue, and corrective glasses should be worn. However, patients with high astigmatism have an intolerance to eyeglasses.
2. Contact lenses, OK lenses, RGP: directly attached to the eyeball, without the cover of glasses, so it can provide a wider field of vision. A tear lens can be created between the lens and the cornea, which can achieve the desired correction of high astigmatism.
3. Surgery: For high astigmatism caused by congenital or acquired factors, it can be treated by corneal refractive surgery (including corneal laser surgery, non-corneal laser surgery), intraocular refractive surgery including lens posterior chamber toric surface (Toric), intraocular lens implantation and refractive lens exchange.
In short, astigmatism is
Higher myopia in a certain direction,
So astigmatism and myopia
The correction method is the same.
Astigmatism is irreversible,
It is possible to change throughout a person's life,
Whether it's a child or an adult
Have regular refractive examinations,
If there is any abnormality, timely intervention and treatment will be carried out.
Character: 卫健
Editor: Xi Yuxuan
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