Many parents ask me, children’s vision examination is normal, need to do optometry? Let’s take a look at the normal development of the eye: the refractive state of a person is different at different ages. When a child is born, the human eyeball is very small, the diameter of the eyeball – that is, the eye axis, is also very small, so the newborn because the eyeball is small, the object through the refractive system of the eye are imaged in the retina after the eye, are farsighted. As the body grows and develops, the eyeball is getting bigger, the eye axis is getting longer, and the visual axis is gradually approaching the normal adult’s eye axis of 23~24mm, which makes the eye orthoptic. Basically, the development of the eyeball is divided into two periods: the rapid development of the eyeball: birth ~ 3 years old, at this time, the rapid development of the eye axis from 16mm to 19, 5mm, is the sensitive period of development of visual function; slow development: 3 years old ~ 18 years old, at this time, the eye axis of 19, 5mm gradually develops to 23mm ~ 24mm. if the eye axis does not reach 23mm, the formation of farsightedness; If the eyeball continues to grow, the eye axis continues to get longer, the object of the eye will become orthopic. If the eyeball continues to grow, the eye axis continues to grow, the object image through the refractive system of the eye in front of the retina, the formation of myopia and every additional 1mm will produce 300 degrees of myopia. Therefore, children’s refractive error and naked eye vision are different at different ages. Therefore, most parents believe that “if a child’s visual acuity is less than 1.0, he/she has poor vision” is wrong. So how much vision is normal for a child? It can be seen that before the age of 6, children’s normal vision is generally below 0, 8, the younger the normal vision standard “the worse”! Parents do not need to worry about their children’s vision not reaching the “normal standard of 1 or 0”. What is the normal refractive power of eyeglasses for children? Age Refraction Naked eye vision 3 years old +1,75～+2,00D 0,6 8 years old +1,25～+1,50D 0,8 12 years old +0,75～+1,00D 1,0 Normal refractive error in children This criterion indicates that normal children’s refractive error is hyperopia. If a child’s eye refraction is not within this normal range, then he or she may have a refractive error (myopia)! This is why it is important for school-age children to have an optometry test, regardless of whether they have good or bad vision, in order to determine whether their vision is developing normally. Since hyperopia can be compensated for by a child’s strong lens regulation, we have to paralyze the ciliary muscle to remove the regulatory influence of the lens to check its true refractive status – called “dilated optometry”. A 7 year old child with a naked eye visual acuity of 0.8, which was considered normal by the school, was found to have a refraction of -0.25DS-1.2 by dilated optometry at Tianming Optometry, which indicates that the normal refraction should be about +0.75D, but the actual refraction was -0.25DS, which indicates that as the eye develops, the eye axis continues to grow, which means that the refraction of the eyeballs will increase. The actual refraction is -0,25DS, indicating that as the eyeball develops and the eye axis continues to grow, this child will definitely develop myopia in the future! At this point, even though myopia is not occurring at the moment, parents should pay attention to it immediately and give their children good myopia prevention. This is why we are able to detect “early signs of myopia” and intervene at an early stage. There are also some cases where the visual acuity is normal, but in fact it is a specific type of refractive error. 1, astigmatism: some low degree (2, 00DC) below the astigmatic eye, can be “squinting” method to improve the naked eye vision. We have seen 400 degrees of astigmatism through “squinting” vision almost to 0, 8, while the normal open eyes to see the situation is only 0, 2. 2, hyperopia and visual fatigue: Hyperopia can be compensated for by the adjustment of the lens, so the general visual acuity examination is often undetectable. However, high hyperopia is often accompanied by visual fatigue, which can be detected and dealt with through standardized optometry examination. 3. Conical cornea: Early and eccentric conical cornea does not affect vision at all, which cannot be detected by simple vision examination, often resulting in a misunderstanding of the condition. We once accidentally found a young boy with cone cornea who accompanied his mother to the lens, his naked eye vision 1, 0, but we found a typical corneal cone in the process of optometry, corneal topography further confirmed the diagnosis. We promptly explained and communicated with the parents, and promptly treated the child with RGP, and the cones changed little over 2 years of follow-up. Recent studies have shown that the incidence of cone cornea is high, with an incidence of 1/2000 in Asia; it is receiving more and more attention. Most patients with conical cornea are preferred to be found in the process of optometry, so optometrists should have more knowledge to avoid delaying the patient’s condition.