In China, the prevalence of myopia among adolescent students remains high and tends to rise gradually and at a younger age. This has caused widespread concern and worries among parents, schools and society, which are eager to find various methods and measures to control myopia. In the past decade, a large number of myopia prevention and control products also came into being, mixed, it is difficult to distinguish the authenticity, and false, exaggerated propaganda, such as “wear” x x mirror “for half a year, vision improved by 4 lines, and do not wear glasses can also see clearly”; wear “x x mirror “
Myopia well”; “not length, reduce the number of glasses”; “signed a one-year trial agreement, the commitment to refund the invalid” and so on abound, resulting in many students and parents due to the lack of correct eye care knowledge, ignorance, prejudice and some of society’s misguided sway. Therefore, we would like to briefly introduce the more common myopia prevention and control methods, principles, applicable conditions and misconceptions, so that parents will no longer blindly choose such products.
I. Progressive lenses for adolescents
Principle: Progressive multifocal lenses, invented by the French, were the first lenses used for presbyopia in middle-aged and elderly people. The principle is the gradual transition between the distant degree above the lens and the near degree below the lens through gradual changes in refractive power, so that the lens can meet the requirements of seeing objects at different distances from far, medium and near. The principle of myopia prevention and control for adolescents is based on the theory that prolonged close use of the eyes and excessive use of accommodation are the causes of myopia and deepening myopia, so that less or no accommodation is used when looking close.
Misconceptions: This youth progressive lens is the theoretical basis for most of the myopia prevention and control lenses on the market today, also known as intelligent zoom, digital zoom, with control myopia treatment myopia and other magical functions and is widely used.
The first misconception is that all myopic patients can use them; in fact, the scope of application of these glasses is very narrow, only for patients who have adjustment tension and adjustment spasm after astigmatism examination, which is often referred to as pseudomyopia. The old theory is that myopia is caused by over-regulation, but new international research data shows that myopia with over-regulation is rare, instead most myopia is caused by poor regulation of the eye, and the lagging regulation cannot form clear images on the retina, thus stimulating excessive scleral growth. The use of progressive multifocal lenses for this group of patients is like adding insult to injury, which will make the lagging phenomenon more serious and accelerate the development of myopia. Therefore, progressive lenses for adolescents must be fitted on the basis of dilated eye examinations and adjustment power examinations (including positive and negative relative adjustment, adjustment magnitude, etc.). In addition, for axial myopia, refractive myopia also does not have a role.
Myth 2: The magical effect of reducing myopia or even treating myopia and taking off glasses; in fact, progressive lenses only have the auxiliary function of relieving visual fatigue after reasonable prescription, and true myopia is mostly a long eye axis, unless the surgical method is impossible to make the elongated eye axis shorten. Businesses are taking advantage of the fact that many parents do not want their children to wear glasses, and even confuse uninformed consumers with promises, contracts and other advertising methods. We have seen many such patients in the clinic who, after wearing these glasses, were told each time they went for a review that they had not developed. When the child can’t see well, he or she goes to the hospital and finds out that myopia has developed to four or five hundred degrees, with complications such as misalignment of the eyes and poor corrected vision. Only then did he realize that it was too late to regret.
Second, the reduction mirror
Principle: prism-convex combination mirror. With a convex lens instead of the eye near the regulation, with a trigonal prism instead of collection, using the principle of refraction of light, changing the visual direction of the near object into the eye, eliminating the eye near the regulation, collection, pupil reduction of the triple linkage, so that the human eye in the near as far as the eye, thus reducing eye fatigue when looking at the near.
Misconception: All myopic patients can use them without adverse effects. In fact, these glasses, like progressive lenses, are only suitable for patients with regulatory tension and regulatory spasm. And there are strict requirements for the eye position of the applicable people. Because we know that most myopic patients will use less adjustment when they see near, thus also reducing the collection caused by adjustment, so most of the performance is poor collection ability, most of the external oblique or have a tendency to exotropia. If such patients use prism-convex combination lenses to completely eliminate the regulation and assembly of near vision, there will be a risk of exotropia in some patients. Therefore, the use of negative lenses must be used under the guidance of a regular hospital ophthalmologist.
Three, keratomileusis, RGP (high oxygen permeable rigid corneal contact lens)
Principle: Corneal shaping lens is a special hard contact lens (generally known as shaping lens, Ortho-K CL) designed and manufactured with high permeability material into a geometric shape that is inverse to the shape of the anterior surface of the human eye, after wearing on the surface of the eye, it produces a slight compression, slowly changing the shape of the cornea, prompting the central optical area of the cornea to become flat, thus reducing myopia and controlling its rapid development.
RGP is the abbreviation of Rigid Gas Permeable; it is made by using the patented AERCOR technology and fluorine and silicone through CNC lathe precision processing; the main reason for RGP to control the development of myopia in youth is its excellent optics and oxygen permeability, which can reduce the aberration, improve the quality of retinal imaging, and significantly improve the visual correction effect, thus reducing the growth of the sclera of ambiguous visual images. Secondly, RGP also has a mechanical corneal flattening effect, which slows down the growth of the eye axis.
Misconceptions.
Myth 1: It can completely cure myopia; corneal shaping is a reversible process, so it will not cause irreversible deformation of the cornea. The shape of the cornea returns to normal after a month or so of discontinuation. Therefore, keratoplasty is effective in controlling the development of myopia, but it cannot cure myopia.
Myth 2: They are suitable for all myopic patients; keratoplasty lenses are only suitable for people with low to moderate axial myopia. There are also strict requirements for corneal shape, corneal curvature, corneal diameter, astigmatism, and eye health status.
Myth 3: You can buy them as you like with soft lenses. Because of the rigidity and flexibility of the RGP and keratomileusis lens materials, it must be accurately manufactured for the unique shape of each eye, i.e., custom-made for each eye.
The lenses are made to order. Therefore, a thorough eye exam prior to fitting is extremely important to the effectiveness and safety of the fit. These examinations include corneal topography, slit lamp, fundus, refraction and other tests. Therefore, modern keratoplasty is a medical practice, and the examination should be performed in a hospital with relevant examination conditions while under the guidance of a physician before the prescription of keratoplasty lenses.
Fourth, Chinese herbal medicine treatment: mainly includes: Chinese medicine, acupuncture, ear acupuncture and other therapies.
Principle: Through acupuncture and acupressure of Chinese medicine, it stimulates the nerve receptors and peripheral blood vessels around the eye, effectively improves the blood circulation and internal nerve regulation around the eye, improves the blood circulation and metabolism of the eye tissue, and restores the physiological regulation of the eye muscle to restore the normal physiological function of the eye.
Misconceptions: It can cure true myopia; Chinese herbal medicine treatment only has a health care effect but not a therapeutic effect. It is effective in the prevention of myopia and the treatment of pseudomyopia, but has no definite and certain efficacy for true myopia.
In summary, we have briefly discussed several mainstream approaches to myopia prevention and control. In addition, binocular accommodation training is a relatively new method that is gradually being promoted in specialty hospitals because it improves accommodation lag, increases accommodation flexibility, and relieves accommodation spasm.
At present, there is no complete agreement or mature theory on the causes, formation process and correction of myopia. However, in the final analysis, formal examination and diagnosis are needed to determine whether the patient has true or pseudo-myopia; if it is true myopia, a distinction should be made between axial, regulatory, or refractive index myopia, and targeted individualized prevention and control methods should be adopted to achieve twice the result with half the effort. The basis of these prevention and control methods must be based on scientific and accurate optometry and reasonable prescription lenses.