Myopia can be divided into several types. Myopia refers to a refractive state where, when the eye is not accommodating, parallel rays of light are refracted by the eye's optical system and the focal point falls in front of the retina. Therefore, people with myopia cannot see distant objects clearly... Myopia mainly leads to a gradual decline in distance vision. Femtosecond laser surgery for myopia, blurred vision of distant objects, normal near vision, but high myopia often causes both distance and near vision problems due to the opacity of the refractive medium and degeneration of the retina and choroid. Sometimes it is accompanied by floating black shadows in front of the eyes.
The following are the types of myopia:
(1) According to the degree of myopia:
- Those within 3.00D (300 degrees) are called mild myopia.
- Those between 3.00D~6.00D (300 degrees~600 degrees) are moderate myopia.
- Those above 6.00D (600 degrees) are high myopia, also known as pathological myopia.
(2) According to refractive components:
- Axial myopia, caused by excessive development of the anterior-posterior axis of the eyeball.
- Curvature myopia, caused by too strong curvature of the cornea or lens surface.
- Refractive index myopia, caused by excessively high refractive index of the refractive medium.
(3) Pseudo-myopia: Also known as accommodative myopia. It is caused by the failure to relax accommodation when looking at distant objects. It has fundamental differences from true myopia caused by changes in refractive components.
(4) Mixed myopia: Often, a person's myopia is caused by eye fatigue leading to pseudo-myopia, which gradually results in partial true myopia coexisting with pseudo-myopia. In short, among those whose myopia degree continues to deepen, all belong to mixed myopia. Currently, the most effective physical treatment for myopia is surgery, which has the advantage of quick results.
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