With the high myopia rate of children and adolescents, parents pay more and more attention to their children's vision. In recent years, the popularity of OK lens has risen again. The professional doctor said that the OK lens can only control the degree, and can not cure myopia. The patient should do the corresponding examination before wearing the OK lens to ensure that it meets the requirements. After wearing the OK lens, they should also do the follow-up observation. In addition, it is more important to develop good eye habits to prevent myopia.
"Compared with the left eye, the eye axis increased by 0.17 mm 3 months before wearing OK glasses, and slowed down to 0.03 mm in these 3 months." Walking out of the ophthalmic consulting room of a class a hospital in Beijing, Chen Maichang sighed with relief and thought, "the 'small glasses' at home can be saved."
Last year, her 8-year-old daughter Xixi began to squint at things. Chen Mai took her to an optometrist to know that she had developed 150 degree myopia in both eyes. After the initial panic and self reproach, Chen Mai followed the doctor's advice and chose the OK mirror for Xixi.
June 6 is the national eye love day. According to the data of the National Health Commission, the overall myopia rate of children and adolescents in China is 52.7%. In order to alleviate children's myopia, some parents place their hopes on OK glasses. What is the principle of OK mirror? Does it work for all children? Will long-term wearing have adverse effects on children's eyes?
OK lens can control the degree but not cure myopia
External application, ear patch, orthodontics... When Xixi just found out that he was short-sighted, he rushed to see a doctor for Chen pulse disease. He tried all kinds of folk prescriptions but had little effect. She was told by the doctor that myopia could not be cured, so she had to intervene as soon as possible to delay the development.
The doctor provided Chen Mai with two intervention schemes, wearing frame glasses or OK glasses, which have the same correction effect. The difference is that the latter only needs to be worn at night, and the control effect is better.
Shen Ling, member of the Chinese children's vision and health care group and chief physician of Dalian women and children's Medical Center, introduced that the OK lens is like a contact lens. It is a hard breathable corneal contact lens. It needs to be worn continuously for 6~8 hours at night, so that the center of the cornea is squeezed and flattened, and it can be maintained all day under the habit.
Shen Ling analyzed that myopia is closely related to the lengthening of the ocular axis and abnormal curvature. When people are about 3 years old, the corneal curvature reaches a stable state, and the ocular axis will continue to grow with their physical development. Therefore, for acquired myopia, controlling the degree is to control the ocular axis.
"Wearing OK glasses is a reversible physical correction. After a period of time, the cornea can rebound to the original refractive state. The change of cornea shape will produce the effect of 'myopic defocus'. In addition to ensuring the central focus, the peripheral light will still be imaged in the retina before releasing the growth signal of' forward adjustment 'to the retina, so as to slow down the growth rate of the ocular axis." Shen Ling said.
According to the guidelines for myopia prevention and control issued by the National Health Commission, long-term wearing of OK glasses can delay the progress of teenagers' ocular axis length by about 0.19 mm / year. This is consistent with Shen Ling's clinical observation: "for every 1mm increase in the ocular axis, myopia increases by about 200~300 degrees. Without intervention, the average child increases by about 100 degrees every year, and the use of OK mirrors decreases by 50~60 degrees on average."
Wearing OK glasses should meet the corresponding conditions
It is understood that the OK mirror technology was introduced into China as early as the 1990s and was once popular throughout the country. However, in just a few years, there were many cases of visual impairment or even blindness caused by wearing OK glasses, which gradually faded out of the public view. In recent years, the heat of OK mirror has risen again. The reporter found that it is "difficult to find No. 1" in the corneal plastic lens clinics of major hospitals in Beijing. Many parents said that "it is necessary to arrange about 10 days on weekdays, and it is impossible to hang up on holidays".
For 28 years, Shen Ling has witnessed the reversal of the public praise of OK mirror. She told the reporter that the problem with the previous OK mirror was that, on the one hand, because the market was mixed, many participants lacked qualifications, and the products were largely imitated. On the other hand, there is insufficient publicity and education. Some parents do not take care of the lenses properly, "for example, to save time, tap water is used instead of cleaning solution, resulting in Acanthamoeba infection."
In recent years, OK glasses have been included in the "three categories of medical devices" for strict management, further clarifying the wearing indications, and developing more perfect fitting specifications.
Shen Ling said that the patient must be over 8 years old. Generally, myopia cannot exceed 600 degrees and astigmatism is not greater than 150 degrees. "If the cornea is naturally flat and the shaping space is small, the allowable degree may be further reduced."
It is understood that the wearer cannot suffer from eye or systemic or systemic diseases. Before fitting, a series of examinations such as slit lamp, optometry, fundus, intraocular pressure, corneal topography, etc. should be done. If the indications are consistent and there are no adverse reactions, the lenses can be customized. After the glasses are provided, the parents should follow the doctor's advice to disinfect and care the lenses and accessories in time, and take the children for a follow-up visit one day, one week and one month after wearing them, and then follow-up observation every three months to ensure that the lenses are consistent with the eye state.
The reporter found that since most of the core materials are imported from foreign countries, the wearing cost of OK glasses remains high. Chen Mai has calculated that the price of a pair of lenses is about 10000 yuan. If they are well maintained, they can be worn for one and a half years. With the daily eye drops and nursing fluids, the total cost of a year is nearly 15000 yuan.
Improving eye habits is more important
For every family, wearing OK glasses is a process of continuous running in. "Mrs. toothpick" is a child care blogger. Her daughter Xiao Hei has been wearing glasses for nearly a year and a half. Although the mother and daughter have established enough tacit understanding, when it comes to the initial "thrilling moment", my mother still has lingering fear, "once she was too nervous, tried to close her eyes, the lens slipped to the bottom of her eyes, making her eyes white and blue, which scared me. After that, she cried and cried for several days without opening her eyes."
"Since the children began to wear this, I have never slept in. After cleaning and taking it off, the adults and children are awake." In order to ensure the wearing time of 6~8 hours, Chen Mai lived the life of setting an alarm clock on the weekend. The doctor asked that she should not rub her eyes or sleep on her stomach. In the first few days, she couldn't sleep well every night. She wanted to stay with Xixi all the time.
Like many parents, Chen Mai gradually realized that wearing OK glasses was just the beginning of this protracted war for myopia prevention and control.
"The occurrence and development of myopia are jointly determined by genetic factors and eye habits. Besides medical intervention, it is particularly important to develop good eye habits." Shen Ling suggested that at least two hours of outdoor activities should be guaranteed every day. High intensity light can stimulate the secretion of dopamine in the eyes and effectively inhibit the growth of the eye axis; Strictly control the time of close eye use, and follow the principle of "20-20-20", that is, after 20 minutes of close eye use (within 5 meters), overlook the scenery beyond 20 feet (6 meters) for 20 seconds; We should also pay attention to the reading and writing posture of "one fist, one foot, one inch", and pay attention to good lighting, balanced nutrition intake and adequate sleep in the room. (some of the interviewees in the text are pseudonyms)