Strabismus is a condition in which the visual axis of both eyes is not correct, with inward, outward or upward or downward misalignment. When looking at an object, the image of the object falls on the macular sulcus of the retina of each eye, and then the brain’s ability to fuse the images makes the images seen by the two eyes become one. Introduction to the dangers of strabismus The first is the effect on appearance, which is the main motivation for patients to seek medical attention. More importantly, strabismus affects the visual function of both eyes, and in severe cases there is no good stereopsis. Stereopsis is an advanced visual function that only humans and higher animals have, and it is one of the prerequisites for people to do fine work. Without good stereoscopic vision, people will be greatly limited in their studies and employment. Most people with strabismus also have amblyopia. As a result of long-term gaze in one eye, the other eye will have disuse vision loss or stop developing, and later, even with proper glasses, vision will not be normal. Strabismus in childhood also affects the development of the entire skeleton, such as the compensatory head position of congenital paralysis strabismus, which causes contracture of the neck muscles and pathological curvature of the crest, and asymmetric facial development. 4 reasons why children suffer from strabismus: Strabismus can occur in both children and adults, but the prevalence rate is much higher in children, and the main reasons are the following four: 1. imperfect development: children, especially infants and young children, have imperfect development of binocular monovision, and cannot coordinate extraocular muscles well, so any unstable factors can contribute to the occurrence of strabismus. The monocular function of human is gradually developed later in life, and the establishment of this function, like the visual function, is gradually developed and matured by repeatedly receiving stimulation from external clear images. The establishment of precise fusion function lasts until after 5 years of age, and the establishment of stereopsis is the latest, at 6-7 years of age, to approach that of adults. Therefore, the period before the age of 5 when the monovision function of both eyes is not perfect is the high incidence of strabismus in children. 2. Congenital anomalies: This kind of strabismus is mostly caused by anomalies in the position of the congenital extraocular muscles, abnormal development of the extraocular muscles themselves, incomplete differentiation of the mesoderm, poor separation of the eye muscles, anomalies and fibrosis of the muscle sheaths, and other anatomical defects or nerve paralysis of the innervated muscles. In some cases, the head and face of the baby are damaged by the use of forceps during delivery or the mother exerts excessive force during delivery, resulting in punctate hemorrhage in the brain, and the hemorrhage happens to be in the nucleus of the nerve that governs eye movements, causing extraocular muscle paralysis. In addition, there is also a genetic component, as strabismus is not inherited in all members of the family, and the defect is often passed on indirectly to the next generation of children. Strabismus occurs within 6 months of birth and is called congenital strabismus. It does not have the basic conditions to establish binocular vision and is the most harmful to the development of visual function. The developmental characteristics of the eye make children prone to strabismus: children have small eyes, short eye axes, and are mostly hyperopic, and children have large corneal and crystal refractive forces and strong ciliary muscle contraction, i.e., strong adjustment. Such children need more adjustment force to see objects clearly, and at the same time, both eyes also turn inward with force to produce excessive convergence, which easily causes internal strabismus, and this kind of internal strabismus is called regulatory internal strabismus. 4. Insufficient control of the eye movement center: if the collection is too strong or the abduction is not enough or both exist at the same time, it produces an internal strabismus; on the contrary, if the abduction is too strong and the collection is not enough or both exist at the same time, it produces an exotropia.