Myopia is divided into simple myopia and pathological myopia. Simple myopia has no fundus changes and can be corrected to obtain ideal corrected vision. When the myopic refraction is greater than 6.0D, it is called high myopia. Pathological myopia is a combination of other histopathological changes in the eye in addition to abnormalities in the refractive system, resulting in varying degrees of vision loss that cannot be corrected to obtain good corrected vision. Highly myopic eyes are called degenerative myopia or pathological myopia only when degenerative changes occur in the fundus of the eye as the eye ages and the axis of the eye lengthens. Epidemiology shows that 12%-15% of myopic patients have a refraction of more than -6.0D, accounting for 2% of the entire population, and 70% of high myopia has vision-threatening ocular pathology. The dilatation of the eye in high myopia can progress slowly over a lifetime and produce a series of complications such as fissured retinal detachment, retinal splitting, lacunar fissures, and macular fissures, ultimately leading to irreversible loss of vision. High myopia causes binocular and monocular blindness and low vision, which seriously affects the quality of vision and quality of life of this population, and brings physical, mental and economic losses to the society and family. Most patients with high myopia already have poor corrected visual acuity with various complications at the time of consultation; therefore, it is especially important to perform early screening among those at high risk of high myopia so that pathological changes can be detected and treated aggressively.