Childhood is a critical period for visual acuity and binocular vision development, and the appearance of strabismus during this period can seriously affect the normal visual development of children. The first is the impact on visual development. When one eye is in a strabismus position, it can cause discomfort such as double vision or confusion in vision, and the brain will actively inhibit the strabismic eye, allowing its visual acuity to reach 0.1 or even lower. Over time, in children with monocular strabismus, the development of the strabismic eye is affected and amblyopia is formed. Treatment of this type of amblyopia is more difficult and in some cases not even completely curable. The second is the impact on the development of binocular vision. Normal binocular vision is an advanced visual function in which both eyes see things simultaneously to form a sense of stereo. It is the basis for the child to be able to perform fine and complex tasks in the future. Binocular vision needs to be gradually developed and perfected in a normal visual environment. The earlier the strabismus appears, the greater the impact on binocular vision. 6 years old is the critical period for binocular vision development, and it is best to have surgery or compression trigeminal lenses to correct strabismus during this period.