What should parents do if they discover that their child has refractive error?

With the arrival of summer vacation, after a semester of hard study, children have ushered in a "crazy vacation" with TV and electronic products. So how are children's eyes? What can parents do during the vacation? What is refractive error? What bad habits can make it worse?

1. What is refractive error?

Children's refractive errors are usually divided into myopia, hyperopia and astigmatism. When the eye stops adjusting, the parallel light from the outside world is focused on the fovea of ​​the retina after passing through the refractive system of the eye. This refractive state is called emmetropia. If the light cannot be focused on the fovea of ​​the retina, a clear image cannot be produced, which is called refractive error.

Children with myopia cannot see distant images clearly, and children with astigmatism see double images. The visual quality of hyperopic children is related to the degree of hyperopia and the adjustment ability of the ciliary muscles. When the degree is small and the adjustment power is strong, both distant and near images can be seen clearly, but as the degree increases and the adjustment power weakens, it may eventually be impossible to see both distant and near images clearly.

Hyperopia means the focus falls behind the retina, but the ciliary body can move the focus forward to a certain extent by adjusting the lens, which is why children with hyperopia can see clearly both near and far in the early stage. Astigmatism is when parallel light rays enter the eye, but due to the different refractive powers of the eyeball on different meridians, they cannot be focused on one point (focus), and the front and back intersection lines form an elliptical optical section, which also cannot form a clear image. Therefore, we wear glasses to use the refraction of the lens to adjust the light to focus on the retina. Myopia and hyperopia are corrected with spherical lenses, the former is a concave lens, and the latter is a convex lens, while astigmatism is more complicated and requires a cylindrical lens.

2. Examination of refractive error

If a child has refractive errors, it will affect their vision and even make their eye condition worse. Therefore, refractive errors should not be underestimated. What should we do?

First, through vision screening and optometry, it can be determined whether it is "refractive error" or other reasons; second, if it is indeed refractive error, it should be known that the change in eye shape is irreversible, and glasses must be worn to use the refraction of the lens to move the focus of the image back to the retina;

To wear glasses correctly, first, the optometry should be accurate. For hyperopia, the pupil should be dilated to relax the ciliary muscles and get the accurate degree. Second, the glasses should be fitted. A pair of qualified glasses should be clear, comfortable and long-lasting.

Physiological hyperopia will gradually turn into emmetropia as the child grows and develops. During this process, it is necessary to ensure good nutrition and close observation. In addition, unlike the standard normal values ​​for adults, children are in the growth and development period, and their refractive error changes rapidly. They must have regular follow-up visits to avoid aggravation of the refractive error due to failure to adjust the treatment plan in time.

3. Bad habits that may cause myopia in children

1. Not enough time for outdoor activities

Increasing the time spent outdoors is the most effective and economical way to prevent and control myopia. Outdoor activities are mainly related to dopamine in preventing myopia. Higher light levels outdoors will promote the eyes to release more dopamine, slow down the growth of the eye axis, and thus play a role in preventing myopia. In addition, strong light exposure outdoors will cause the pupil to shrink, the depth of field to deepen, and the blur to reduce, which may also play a role in preventing myopia. It is recommended that children spend at least 2 hours outdoors every day and at least 14 hours per week.

2. Wrong way to use the desk lamp

At present, there is no evidence from clinical medicine to prove that desk lamps can effectively prevent myopia. Various eye protection desk lamps only partially reduce the negative factors that affect vision. According to the national standard for desk lamps, "Performance Requirements for Reading and Writing Desk Lamps", the light source of eye protection desk lamps should be full spectrum, no flicker, moderate color temperature, good color rendering, and a color rendering index of no less than 80.

3. Eating too many sweets

On January 16, 2024, a research result of the team of the Eye and Optometry Hospital Affiliated to Wenzhou Medical University revealed that glycolysis activation is the key molecular mechanism for the remodeling of the scleral extracellular matrix to induce myopia, and provided potential new targets and strategies for the prevention and control of myopia. According to the research results, children who eat more sugar will soften their eyeballs, and their eyeballs have not yet fully developed. Softened eyeballs are prone to hypoxia and elongation, leading to the occurrence and development of myopia. The researchers also found that close-range eye use can also cause the occurrence and development of myopia by inducing scleral hypoxia, and has an additive effect with a high-sugar diet. Therefore, parents should not only control the amount of sugar their children eat, but also advise their children to avoid or minimize close-range eye use within 1 hour after a meal. Otherwise, the surge in postprandial insulin and the hypoxia caused by close-range eye use will deal a double blow to the eyeballs.