I. Myopia Survey DD Statistics from the Ministry of Education
The myopia rate among students remains high, and the trend of its low age is particularly worrying
To cultivate high-quality talents to meet the needs of the 21st century, physical and mental health is the foundation. According to China Education News, November 10, 2001, page 3, in 2000, the results of the fourth national student physical health survey jointly organized by five ministries (bureaus), including the Ministry of Education, the Ministry of Health, the State General Administration of Sports, the Ministry of Science and Technology, and the National People’s Committee, showed that the myopia rate among students remains worryingly high. The myopia rate among primary school students is 20,23%, 48,18% among junior high school students, 71,29% among high school students, and 73,01% among college students. Compared to 1995, while myopia rates in elementary, middle school, and college have stabilized, with some age groups (e.g., 10-14 years old) showing decreases, myopia rates among 16-18 year old high school students have increased from 66, 80% to 71, 29%. The prevalence of myopia among Chinese students ranks second in the world after Japan. In 2001, 99% of 300 college students in Tianjin who were recruited into the military failed the physical examination, with myopia being the main limiting factor. Since myopia is one of the main causes of blindness, it will seriously endanger the health of the next generation and even the rise and fall of the nation and the safety and security of the country. Therefore, myopia has become a major social issue of concern to everyone [1~9].
Environmental factors are the main cause of myopia in students
Experimental and clinical research on myopia, which began in the late 1970s, has made significant achievements over the past two decades [10-21]. Studies have shown that although there are important genetic factors, environmental factors play a major role in simple myopia, which accounts for the majority of myopia in students, and even in the minority of pathological myopia, environmental factors also play an important role. The main reason for the high rate of myopia among students is the excessive burden of school work and the long time spent in close proximity to the eyes. With the prevalence of video games, the popularity of computers, the development of network information, primary and secondary school students spend a long time playing video games, surfing the Internet, watching TV, etc. is also an important factor leading to the occurrence of myopia in Tong Ren Eye Center.
Only a small part of myopia in adolescents is due to genetics, but most of it is caused by improper use of the eyes. The development of myopia is related to the use of eyes at close range, insufficient lighting, long hours of eye use and incorrect posture. Due to the secretion of growth hormone and the instability of the endocrine system, most of myopia occurs and develops in the age group of 12 to 18 years old, while the development of myopia will gradually slow down or stop at the age of 18 to 20 years old after maturity.
Good hygiene and eye habits are necessary to ensure students’ vision health
Article 2 of the Regulations on School Health Work issued in 1990 stipulates that schools should monitor the health status of students; provide health education to students and cultivate good health habits; improve the school health environment and teaching health conditions; and strengthen the prevention and treatment of infectious diseases and common student diseases. Article 6 stipulates that: school teaching buildings, environmental noise, indoor microclimate, lighting, lighting and other environmental quality, as well as blackboards, desks and chairs should be set to meet the relevant national standards.
In addition, it should be noted that China’s school classroom lighting standards are in urgent need of revision. The International Commission on Illumination set the average illumination of classrooms should be at a minimum of 300 lux, normal for 500 lux, and laboratories should reach 750 lux. China’s current “lighting and lighting health standards for primary and secondary schools” was issued and implemented by the Ministry of Health in 1987, which stipulates that the average illumination of student classrooms is only 150 lux, which is obviously lower than international standards. Therefore, efforts should be made to improve the illumination level of classrooms.
From the time students enter school, they should be taught to develop good habits: read and write with proper posture, keeping the distance between the eyes and the writing at 30-40 cm or more; for every 30-40 minutes of reading and writing, they should go out for activities or look away for 10 minutes to avoid prolonged close eye use; not to read while walking or riding in a car; and not to read and write in places where the light is too weak or too strong.
Physical exercise is a necessary tool to enhance students’ vision health
Schools should, according to the “Regulations on School Physical Education” with the geographical and climatic conditions of each place with the actual situation of the local
Seriously carry out a rich and colorful teaching of physical education classes, and should organize lively extracurricular sports activities for students to ensure that they have one hour of physical activity every day. Correct eye exercises are very important to prevent myopia in students.
The earlier the prevention of myopia, the better, and it should be continued at least throughout the schooling period.
The establishment of an animal model of lens-induced myopia and the inhibition of orthokeratology in animals by lens correction suggest that pathological myopia, including infancy and even congenital onset, can be prevented and controlled [10-16]. In infancy, the average axis length of the eye increases from 18.0 mm at birth to 22.8 mm at age 3. During the adolescent growth period (3-14 years), the axis length increases by only 1 mm, which means that the critical period of visual development from birth to age 3 is also a highly sensitive period for the prevention and control of pathological myopia. Researchers at the Massachusetts Institute of Technology (MIT) in the United States have concluded from long-term studies that optometry for children under 1 year of age can tell whether they will become myopic in the future, and that myopic infants under 1 year of age are most likely to become myopic in the future, although there is a tendency for them to become orthopic in the next 3 to 4 years. Therefore, it is believed that a series of eye examinations can predict whether a child will develop myopia in the future within 1 year of age, and if detected early, it can be prevented as early as possible [16]. 3 to 6 years of age is a sensitive period for myopia prevention, and up to 14 years of age is an important period for myopia prevention. However, in recent years, the increase in close work has delayed the age of stabilization of many myopes until after 20 years of age, and the occurrence of adult myopia is increasing. Therefore, myopia prevention should be continued at least until the end of college education.
Misconceptions about myopia prevention in adolescents
1. The proportion of pseudomyopia in adolescent myopia is exaggerated
Myopia is a condition in which parallel light is refracted by the refractive system of the eye and focused on the retina before it can form a clear image on the retina, resulting in reduced visual acuity. Therefore, this type of myopia, or what we usually call true myopia, has a stationary refractive state, and the growth of the anterior and posterior diameters of the eye is the basic anatomical change.
In adolescents, due to strong regulation, some myopic patients have regulatory myopia, which is often referred to as pseudomyopia.
When the human eye looks at objects from far to near, the ciliary body contracts and relaxes the suspensory ligament, causing the lens to become more convex and producing accommodation. When looking at objects from near for a long time, the ciliary muscle is contracted for a long time and does not relax, resulting in spasm.
The root cause of the myopia is the spasm of the ciliary muscle, which can be relieved by relaxing the ciliary muscle. The percentage of patients with this condition is not really high, as statistics show that only 8% of our patients have simple pseudomyopia. The current youth myopia is due to various media and businesses exaggerating the component of pseudomyopia in myopia.
This is followed by the emergence of various myopia treatment devices and treatment drugs, which largely mislead patients.
2. Current misconceptions in myopia prevention and treatment
Most of the myopia prevention and treatment drugs sold in the market are Chinese prescriptions, which are broadly divided into two types, one is sold at health care counters, such as the sale of Neptune Pharmaceuticals “Eye Treasure” in the street Tian Yi Tang, the description of the efficacy of this drug is “improve vision”. The salesman told reporters that this medicine can only be used to improve vision and relieve eye fatigue, not as a treatment for myopia. The other is sold at the pill counter, such as a variety of brands of “light-enhancing tablets”, the efficacy of which is clearly marked “treatment of myopia”, pharmacies for the treatment of myopia are mostly recommended for such drugs.
Oral medications do not cure myopia
Many oral medications and eye drops are misleading to consumers in terms of publicity. In principle, there is no scientific basis for medications to treat myopia, and they can only be effective in the short term for maintaining vision and relieving visual fatigue, but long-term use is harmful and unhelpful. Most of these drugs use the principle of inhibition or excitation of the eye ciliary muscle to improve vision in the short term, but this approach only improves the function of distance viewing, but has no effect on the prevention of myopia. The inhibition or excitation of the eye muscle is equivalent to anesthesia, and the eye’s ability to adjust the degree of myopia is reduced in myopia, and can only try to lengthen the axis of the eye, and for every millimeter of lengthening, myopia will be strengthened by 300 degrees, which is very likely to cause irreparable axial myopia.
Many ophthalmologists agree that oral medication for myopia will not be effective. Myopia is a deformation of the eye axis, and this change cannot be reversed by medication. Therefore, there are no medications that can cure myopia, and wearing glasses and having surgery are still the most basic methods of treating myopia. Moreover, the side effects of these drugs cannot be ignored during the growth phase of adolescents
Since there is no very effective way to prevent and treat myopia, more and more people are wearing myopia glasses, and students, parents and society are eager for some ways to control the development of myopia. In order to meet this need, a large number of myopia prevention and treatment eye drugs, oral medications, small devices and various physical therapy means such as ultrasound, magnetic therapy, etc. are dumped in the pharmaceutical market in large quantities. One by one, these myopia prevention drugs or devices are being eliminated because of the lack of recognized and scientific arguments for their effectiveness. In fact, on the one hand, a large number of advertisements advertise the effectiveness of certain drugs or devices in treating myopia; on the other hand, the number of students with myopia has increased dramatically. This fact fully illustrates that the therapeutic effect of those drugs and devices is highly doubtful. Therefore, primary and secondary school students suffering from myopia and their parents must be cautious about whether to use the drugs and devices available in the market for myopia treatment. Not only are they unreliable, but some of them are not only ineffective but may also cause adverse consequences to the eyes.
The treatment of myopia is a major problem in the medical field, and there are various ways to treat myopia on the market in China. The National Student Myopia Prevention and Treatment Expert Steering Group has reviewed more than 50 kinds of anti-myopia supplies, some of which can relieve visual fatigue to improve vision, some have a relieving or therapeutic effect on pseudomyopia, and some can play a role in diagnosing or treating pseudomyopia and preventing true myopia. However, none of the items reviewed had a definite therapeutic effect on true myopia.
Myopia is the most important type of refractive error among the most common conditions in ophthalmology, with a prevalence of about 33% in our population, or nearly 400 million people. Many people believe that there is a difference between true and false myopia, and that false is a reversible or early stage of true myopia, which are actually unscientific concepts. In the first place, except for the 1% of high myopia, the essence of myopia is only equivalent to a camera focus blur from the optical point of view. The physiological requirements for refraction change with age throughout a person’s life, so for the vast majority of myopic patients, there is no need to be overly concerned. The popularity of pseudomyopia reflects people’s eagerness to correct myopia, and is accompanied by certain artificial commercialization factors, which make a wide range of “treatment for pseudomyopia” available, and also make people go further and further away from the scientific treatment of myopia. Therefore, I hope that parents will not blindly believe in this concept, and should take their children to a professional medical institution for diagnosis and treatment as soon as they find that their children have vision problems.
Third, the correct treatment of myopia prevention and treatment of adolescents
Methods of myopia correction for adolescents.
The safest and most effective method for teenagers (under 18 years old) is to wear glasses scientifically and reasonably.
Myth: The more you wear glasses, the deeper they get, and as long as you wear them, you can never take them off.
If you are nearsighted and do not wear glasses, you will have two consequences: one is that it is easy to cause vision fatigue, which affects learning and work; the other is that when you look at something, both eyes often squint into a slit. In the long run, the upper and lower eyelids will compress the eyeball causing a shift in astigmatism, and the front and back eye axis will elongate, making myopia increasing.
If your eyes are nearsighted, you should wear glasses correctly.
Myopic glasses can correct vision. Nearsightedness is caused by the fact that light from far away cannot be focused on the retina, resulting in unclear vision of distant objects, and with nearsightedness glasses, a clear image can be obtained, thus correcting vision.
Nearsightedness can reduce visual fatigue. Myopia and not wearing glasses, will inevitably lead to glasses easily fatigue, the result is only to promote the degree of deepening. After normal wearing glasses, the phenomenon of visual fatigue will be greatly reduced.
Nearsighted glasses can prevent and control exotropia. When myopic eyes are near, the regulation of the eye is weakened, and the role of the straight muscle outside the eye exceeds that of the straight muscle inside for a long time, which will cause the eye position to be exotropic. Of course, myopia with exotropia can still be corrected by myopic lenses.
Myopic lenses can prevent eye protrusion. As the eye is still developing, myopia can easily develop into axial myopia. Especially in highly myopic eyes, the anterior and posterior diameters of the eye are significantly lengthened, and the appearance is manifested as protrusion of the eye, which can be reduced, or even not occur, if myopia is corrected with normal lenses at the beginning.
Myopic glasses can prevent amblyopia, high myopia and not timely wearing glasses, often resulting in refractive error amblyopia, as long as the appropriate glasses, after a longer period of treatment, most of the vision will gradually improve.
Myopia glasses have a preventive effect on high myopia-induced comorbidities, such as retinal detachment, vitreous opacity, cataract, glaucoma, nystagmus, etc.
Therefore, myopic patients should choose a regular optician, as long as the glasses are properly fitted, worn from time to time, and pay attention to daily vision hygiene, the myopia can be stabilized or even reduced.
Myopia correction for adults (over 18 years old).
Wear the right glasses and, if necessary, undergo myopic refractive surgery.
What is the best way to get the right pair of glasses?
There are 5 simple principles.
1, vision loss, first of all, should be examined by an eye specialist to exclude other eye diseases;
2, refractive error must be prescription lenses, should first check the shadow (primary examination), no contraindications to the best full dilated pupil examination shadow, in order to get accurate objective refraction; for complex refractive state should be medical optometry when necessary.
3, before the prescription must also be re-tested, that is, in the case of non-dilated try on glasses. The objective optometry slightly adjusted to make the subjective feeling comfortable, so that you can choose the best acceptable diopter;
4, purely rely on computerized optometry prescription method is actually undesirable, it is difficult to be accurate for adolescent myopia.
The key is: accurate optometry.
Exclude pure computerized optometry
Advocate to hospitals and regular optical stores for optometry.
Exploration of myopia prevention and treatment at home and abroad
1. The effect of wearing bifocal or progressive multifocal lenses on the control of myopia in students with DD needs to be clinically verified on a larger scale.
For those who have already developed myopia, especially those with moderate myopia or above, it is recommended to give bifocal glasses for correction, which can reduce the need for adjustment when wearing glasses for near vision and help inhibit the development of myopia [1,2,23~25]. Recently, FulkGW [26] and others at the Northeastern University College of Optometry have demonstrated that wearing bifocals has a significant inhibitory effect on fast-progressing myopia in children with near-point internal prosopagnosia. ChiangMF [27] from the Wilmer Eye Institute at Johns Hopkins University, SyniutaLA [28] from the Jules Stein Eye Institute at the University of California, Los Angeles, and RomanoPE [29,30] have shown that wearing bifocals combined with low concentrations of atropine dots can significantly inhibit the development of myopia in students, which has However, the side effects of atropine should be noted [31]. The clinical observation of more than 2000 cases of myopia in students in the last two years at the Beijing Shang Shang Medical Myopia Research Center also showed that for mild myopia, bifocals can be worn only during class and homework, and they are easy to fit and adapt, and the combination of low concentration atropine spotting can effectively control the development of myopia in young students.
In 1999, LeungJT et al [32] from Hong Kong Polytechnic University reported that progressive lenses had an inhibitory effect on the development of myopia. However, the reliability of the results was affected by the presence of small sample size, the absence of double-blind method, and the absence of ciliary muscle paralysis under optometry [33,34]. A study by ShihYF et al [35] from the ophthalmology department of National Taiwan University Hospital in Taiwan showed that progressive lenses combined with 0,5% atropine spotting significantly inhibited the progression of myopia in adolescents, however, the effect of progressive lenses alone was not significant. Since 1996, four schools of optometry in the United States have jointly embarked on a study of the effect of progressive lenses on the progression of myopia in adolescents (COMET), which is also being conducted in Beijing, Shanghai, Tianjin, and Wenzhou, China [33,34]. The current final summary has been completed and no reliable results for myopia control have been produced.
Therefore, studies on bifocal and progressive multifocal lenses for myopia control in adolescents are still in progress and inconclusive.
2. Wearing gas permeable rigid glasses (RGP) may help control myopia progression in students
Since the 1950s, with the promotion of PMMA plastic hard lenses, it was found that the lenses had the phenomenon of inhibiting or delaying the progression of myopia in children. in the late 1970s, RGP was introduced, and its breathable performance and safety performance continued to improve, rapidly replacing PMMA hard lenses. Since the late 1980s and early 1990s, optometrists have been systematically studying the effect of RGP on the progression of myopia in children [25,33,37-39]. KhooCY et al [38] from the National Eye Research Centre in Singapore showed that RGP significantly inhibited the progression of myopia in adolescents.The excellent optical properties of RGP may contribute to myopia stabilization [25,33,37,38]. However, a 50% or more missed visit rate cannot but affect the reliability of the results [25,37]. The critically designed Contact Lens and Myopia Progression (CLAMP) study is still in progress [39]. There is a lack of substantial clinical evidence to support this.
OK lenses are a special type of RGP with a flat central and steep peripheral “reverse geometry” design that flattens the central cornea and reduces refraction by mechanical compression; however, they do not cure myopia and return to the original refraction after discontinuation of lenses [25,33,40]. When wearing OK lenses for myopia correction, the cornea is under pressure, especially when the lenses are worn at night, and corneal abrasion as well as corneal infection may occur at any time. Therefore, OK lenses must be fitted in a qualified medical unit under the guidance of a trained ophthalmologist and be reviewed strictly and regularly [25,33,40].
3. Refractive surgery to correct myopia in students should strictly grasp the indications
Excimer laser refractive keratomileusis (PRK) is indicated for patients older than 20 years with mild to moderate myopia and normal corrected visual acuity, who have had stable myopia for 2 years and who voluntarily undergo surgery. The indications for excimer laser in situ keratomileusis (LASIK) are largely the same as those for PRK, but with a larger range of correctable refractive errors; PRK and LASIK are currently the main clinical treatments for refractive errors in ophthalmology, but the intraoperative and postoperative complications of this procedure should be of great concern to ophthalmologists.
LASIK can be used to correct myopic refractive aberrations in children. Children with high monocular myopia treated with LASIK can contribute to the development of stereo vision and amblyopia prevention. In addition, PRK and LASIK are effective in correcting hyperopia and have a special therapeutic effect on hyperopic amblyopia in children [41].
In a few pathological myopic eyes, posterior scleral reinforcement can be used to strengthen the scleral resistance and stop myopia progression in its early stages of development.