Everyone is talking about myopia, but do you really understand myopia?

Abstract: refractive myopia: refers to myopia caused by abnormal refractive medium and excessive refractive power due to normal axial length. Refractive myopia is divided into curvature myopia and refractive index myopia.

myopia is not only a hot topic, but also an eternal topic. The incidence of myopia is increasing year by year in recent years, and it is getting younger. Myopia has become an increasingly serious problem endangering people’s health.

classification of myopia

1. Classification according to the degree of myopia.

(1) mild myopia: – 3.00d and below, that is, we usually say myopia of 300 degrees and below.

(2) moderate myopia: – 3.00d to -6.00d, that is, we usually say myopia of 300 degrees to 600 degrees.

(3) High myopia: – more than 6.25, that is, myopia above 600 degrees as we usually call it.

2. According to the classification of refractive components,

(1) Refractive myopia: refers to myopia with normal axial length, but caused by excessive refractive power due to abnormal refractive medium. Refractive myopia is divided into curvature myopia and refractive index myopia.

(2) Axial myopia: refers to myopia caused by parallel light converging in front of the retina after entering the refractive system due to the extension of the eye axis.

3. Classification of

(1) simple myopia: refers to myopia caused by hypermyopia during development. Most refractive errors are -6.00d (commonly known as 600 degrees).

(2) pathological myopia: it refers to those whose eyeballs are still developing and have pathological changes after the age of 20, also known as progressive myopia.

4. Classify

according to whether dynamic refraction is involved (1) Pseudomyopia: it refers to myopic ametropia disappears and becomes emmetropia or mild hyperopia after atropine mydriasis.

(2) true myopia: it is commonly referred to as myopia, which refers to myopic ametropia does not decrease or the degree of reduction is less than 0.05d after atropine mydriasis.

(3) Mixed myopia: it refers to the examination after atropine mydriasis. The refractive error of myopia is significantly reduced, but it does not return to emmetropia.