According to the data provided by the National Office for the Prevention and Treatment of Myopia in Primary and Secondary School Students, the myopia rates of primary, middle and high school students are 13.35%, 37.4% and 61.5% respectively. With the development of modern technology and the popularity of electronic products, children need to use their eyes not only for reading, but also for leisure time. The prevalence of myopia is increasing and is trending toward a younger age. China is the undisputed myopic country, and the latest research data shows that there are 400 million myopic patients in China, of which 56% are low and medium myopic and 44% are high myopic (myopia of more than 600 degrees). High myopia is often accompanied by pathological changes in the eye due to the prolongation of the eye axis, leading to varying degrees of visual impairment and even blindness. Myopic blindness is the sixth most common eye disease in China. The number of people who become blind due to myopia is 300,000. The impact of myopia on youth and national health is self-evident. So, how myopia is formed, what factors are related to it, and how to treat and prevent it. Myopia is a condition in which parallel light from external objects passes through the refractive system of the eye and forms a focal point in front of the retina when the eye is relaxed and unregulated. This means that myopic eyes can only see objects within a limited distance of 5 meters in front of them, and cannot see distant objects. The greater the degree of myopia, the closer the object must be to the eye in order to see it clearly. Therefore, we can roughly know the degree of myopia by observing the distance a person is reading a book or newspaper. There are two types of myopia: simple myopia, also called school myopia, is related to excessive eye use and lack of eye hygiene. It usually occurs at the age of 8-12 and stabilizes around the age of 18, usually not exceeding 1000 degrees. The other type of myopia is pathological myopia, also known as progressive hyperopia. The onset is early, often before the age of 8 years, and increases with age. There are genetic factors. Persistent progression of myopia will lead to pathological myopia as well as other complications and eventually blindness. Individuals with pathological myopia often have reduced visual acuity and may have complications such as severe strabismus, open-angle glaucoma, and lens clouding. High myopia is the more severe form of myopia, usually with a refraction above -6.00 D and with fundus damage and corrected visual acuity of less than 1.0. High myopia is extremely common in Asia and the Middle East. In many developed countries, high myopia has become a major cause of blindness, with the incidence of high myopia in Western Europe and the United States ranging from 0.5% to 2.5%, second only to diabetes as a major cause of blindness in the population. At present, the main methods of myopia correction for high myopia are: frame glasses and hard and soft contact lenses, excimer keratomileusis and refractive lens replacement and intraocular refractive surgery such as IOL implantation. Each of these methods has its own advantages and disadvantages. 1. Frame glasses, which have the advantages of convenience and economy. However, wearing them on the eyes will restrict the field of vision, and glasses with large prescriptions will also distort the vision. If you don’t have a proper fitting by an optometric professional, you may also accelerate the progress of myopia and discomfort. The effect of frame glasses is not good because of the high degree of pathological myopia, one is too thick lenses, visual deformation, halo, and ugly appearance. 2, contact lenses, because soft lenses are not oxygen permeable, too much damage to the cornea, not suitable for regular wear. Rigid contact lenses RGP is a better choice among non-surgical methods. It is also the most optically effective of all refractive correction methods. Therefore, it is also the best refractive correction method to control the progression of myopia. 3, excimer keratomileusis: Excimer laser surgery is to change the curvature of the cornea through the energy of the laser, reshaping the curvature of the cornea, so as to achieve the purpose of treating myopia, hyperopia and astigmatism. In fact, it is the use of high-tech means to carve a contact lens in the cornea of the human eye that will never be removed. Excimer laser surgery for myopia correction has a history of more than 10 years. As the equipment of laser surgery is constantly updated like other electronic products, the safety and reasonableness is more perfect, and laser surgery is an external eye surgery, so it can be said that its safety is relatively high. However, since pathological myopia is generally high, if the degree is too high or the cornea is too thin for ordinary excimer keratomileusis, you can consider individualized excimer surgery to adjust the Q value of the cornea in a more economical way. If the thickness of the cornea is still not enough for excimer surgery, then refractive lens replacement or intraocular refractive surgery such as IOL implantation in crystalline eyes should be considered, and the posterior chamber lens implantation (ICL) in crystalline eyes will be a good choice in these surgeries. 4.ICL: For patients who have been examined for surgical indications but cannot undergo LASIK correction surgery due to high prescription or thin cornea, the most ideal treatment method is ICL implantation, which is now widely used in the U.S. ICL implantation, also known as posterior chamber IOL implantation, is currently considered to be the latest refractive correction technique that can replace other LASIK cutting procedures. It can correct a wider range of myopia, hyperopia and astigmatism without the need for corneal tissue removal and post-surgical sutures, and it can achieve predictable refractive correction and excellent visual quality. It is particularly effective in the treatment of high myopia. Professor Zheng Ling of the Optometry Clinic of the Fourth Hospital of Harbin Medical University has been the first to perform this procedure in the province for nearly three years and has benefited nearly 100 patients with satisfactory results. From the available clinical data, it can be seen that the complications of this surgery are relatively few, and the most concerned are the complications of cataract and intraocular pressure increase. In fact, the incidence of such complications is extremely low and easily controlled. In addition, the reversibility of the procedure is also a feature of the procedure, as a new and more suitable IOL can be removed or replaced depending on the clinical need. As research progresses, in addition to high myopia, IOL implantation has shown good results in the correction of hyperopic refractive errors and hyperopic and myopic refractive errors with astigmatism. It is believed that in the near future, IOL implantation will occupy an important place in many refractive surgeries. There are many refractive surgery methods available today, each with its own advantages, among which LASIK is widely used clinically, but its treatment scope is relatively limited, especially for patients with high myopia, and friends with high myopia have a more urgent desire to get rid of their glasses, but there are many people who are frustrated after examination because their eyes are not eligible for excimer surgery. For people with pathological myopia, safe and effective refractive surgery is not only the icing on the cake, but also the cherry on top. It should be said that ICL brings a new hope and gospel to people with high myopia. It is also worth mentioning that if the patient’s vision changes significantly and the ICL worn is no longer suitable, the ICL can be removed or replaced at any time.