Abstract: the etiology of myopia has a certain genetic tendency, which has been recognized, especially for high myopia. But for general myopia, this tendency is not very obvious. Those with genetic factors had earlier onset age, mostly at 6. Above 00D., Myopia brings a lot of inconvenience to our life. We should prevent it from childhood, not until we grow up. Causes of myopia: internal and external causes, please see the following introduction., 1. Internal causes, genetic quality and the etiology of myopia have a certain genetic tendency, which has been recognized, especially for high myopia. But for general myopia, this tendency is not very obvious. Those with genetic factors had earlier onset age, mostly at 6. Above 00D. But there are also high myopia without family history. High myopia belongs to autosomal recessive inheritance, and general myopia belongs to multifactorial genetic disease., Due to developmental factors, infants are hyperopia because their eyeballs are small, but with the increase of age, the ocular axis also gradually lengthens, and the development is normal until puberty. If overgrowth, myopia will be formed. This kind of myopia is called simple myopia, which mostly starts in school age. Generally less than 6. 00D。 Development stops around the age of 20. If it progresses quickly in childhood, it will progress faster at the age of 15 ~ 20, and then slow down. This kind of myopia is often higher than 6. 00D, up to 20d ~ 25d or 30d. This kind of myopia is called high myopia or progressive myopia or pathological myopia. Such myopia can occur and degenerate in old age, so vision can gradually decline, and vision can not be corrected with glasses. It is rare to have myopia at birth, but very few are congenital., 2. External factors, that is, environmental factors. People engaged in writing work or other close work have more causes of myopia, and there are more myopia among young students. Moreover, the prevalence rate has increased significantly since the fifth and sixth grades of primary school. This phenomenon shows that the occurrence and development of myopia are closely related to close work.,
myopia brings a lot of inconvenience to our life. We should prevent it from childhood, not until we grow up. Causes of myopia: internal and external causes, please see the following introduction.
1. Internal cause
genetic quality
the cause of myopia has a certain genetic tendency, which has been recognized, especially for high myopia. But for general myopia, this tendency is not very obvious. Those with genetic factors had earlier onset age, mostly at 6. Above 00D. But there are also high myopia without family history. High myopia belongs to autosomal recessive inheritance, and general myopia belongs to multifactorial genetic disease.
developmental factors
infants are hyperopia because of their small eyeballs. However, with the increase of age, the ocular axis also gradually lengthens and develops normally until puberty. If overgrowth, myopia will be formed. This kind of myopia is called simple myopia, which mostly starts in school age. Generally less than 6. 00D。 Development stops around the age of 20. If it progresses quickly in childhood, it will progress faster at the age of 15 ~ 20, and then slow down. This kind of myopia is often higher than 6. 00D, up to 20d ~ 25d or 30d. This kind of myopia is called high myopia or progressive myopia or pathological myopia. Such myopia can occur and degenerate in old age, so vision can gradually decline, and vision can not be corrected with glasses. Very few have myopia at birth, but very few are congenital.
2. External factors
are environmental factors. People engaged in writing work or other close work have more causes of myopia, and there are more myopia among young students. Moreover, the prevalence has increased significantly since the fifth and sixth grades of primary school. This phenomenon shows that the occurrence and development of myopia are closely related to close work.
myopia is a multifactorial genetic disease
, especially the eyeball of teenagers. It is in the stage of growth and development, has strong regulation ability, and the ball wall is relatively extensible. It is used for regulation and integration during close work such as reading and transceiver room, Make the external Ken muscle (mainly the internal rectus muscle) exert a certain pressure on the eyeball, and the intraocular pressure increases accordingly. With the continuous increase of work, the frequency and time of adjustment and collection also gradually increase. The ciliary muscle and extraocular muscle are often in a high tension state. The excessive exertion of regulation can cause the ciliary muscle spasm, resulting in temporary vision loss.
However, after rest or use of ciliary muscle erosion agent, vision may improve and recover completely. Therefore, some people call this myopia functional myopia or pseudomyopia. However, under the long-term mechanical compression of extraocular muscles, the scleral wall gradually extends, the ocular axis elongates, the degree of myopia is deeper and deeper, and can no longer be alleviated by atropine.
especially in adolescence, failure to pay attention to visual hygiene is the direct cause of myopia. Not paying attention to general health can promote the development of myopia.