A visual acuity of 4.8 degrees may be caused by myopia, but it may also be caused by hyperopia, astigmatism or eye diseases. 1. Nearsightedness: Nearsightedness will lead to vision loss, it is currently believed that due to a combination of genetic and environmental factors, resulting in the crystalline refractive power of the crystal is elevated or the eye axis is elongated, which will gradually lead to the emergence of nearsightedness. If the eye habits are not good, such as the use of electronic products for a long time, resulting in visual fatigue is one of the factors leading to myopia. 2. Hyperopia: It is produced by parallel light from the far end of the eye passing through the refractive system of the eye and gathering at the back of the retina. If the child is under 6 years old, the eye is not fully developed, the cornea is flat, there is no lens eye or lens dislocation can be indicated as a state of high hyperopia. 3. Astigmatism: a kind of astigmatism formed through the refraction of the refractive system, this kind of astigmatism is caused by any kind of refractive medium of the refractive system of the eye. 4. Eye diseases: some eye diseases can also lead to vision loss, such as cataracts, amblyopia and so on. Therefore, vision 4.8 is not myopia, but also need to go to a professional hospital for optometry, according to the results of the doctor’s judgment and then standardized treatment.