I. What is amblyopia? Amblyopia is a decrease in best-corrected visual acuity in one or both eyes due to abnormal visual experiences (monocular strabismus, refractive aberration, high refractive error, and form deprivation) during visual development, without organic pathology on ocular examination. In the past, children with best-corrected visual acuity below 0.9 in one or both eyes were considered amblyopic, without taking into account the age factor, resulting in the generalization of amblyopia diagnosis. Currently, the Strabismus and Pediatric Ophthalmology Group of the Chinese Medical Association’s Ophthalmology Branch has redefined amblyopia in this regard: amblyopia is diagnosed with reference to the lower limit of normal visual acuity in children of different ages: amblyopia is considered when the corrected visual acuity is below 0.5 in children under 3 years old, below 0.6 in children between 4 and 5 years old, and below 0.7 in children between 6 and 7 years old. Amblyopia is an eye disease that seriously endangers the visual function of children. If amblyopia in children is not detected and treated early, it will lead to low vision in one or both eyes, which will seriously affect binocular vision and lead to fusion loss and stereo blindness. Amblyopia is a curable disease if it occurs during the sensitive stage of visual development. Therefore, the age factor is very critical in the treatment of amblyopia, and early detection, early intervention, and treatment must be achieved. How can parents find out if their child has amblyopia early? 1. Preschool physical examination: In general, children, especially those who grew up in kindergartens, can recognize the visual acuity table at the age of 3 after a simple visual acuity education. Parents can also purchase a standard vision chart and hang it on a well-lit wall at a distance of 5m for their children to identify. If the vision of one eye is below 0.8, the child should be taken to the hospital for further examination. It is generally believed that it is best to check no later than 4 years old. 2, early detection of the first signs of abnormalities. Children with amblyopia often have other manifestations besides low vision, such as strabismus, skewed head, squinting or close to the eyes, etc. Once a child is found to have strabismus, he or she should go to the hospital eye examinations and confirm the diagnosis as soon as possible, because about 1/2 of strabismus combined with amblyopia. Other abnormalities mentioned above should also be taken seriously and checked by the hospital ophthalmology department to see if they are caused by eye disorders. For infants and young children who cannot cooperate with the vision check, a masking test can be done to get a general idea of binocular vision: if one eye is intentionally covered and the child sees with one eye, and if it is quiet and the other eye is crying and restless or tearing and scratching the mask (provocation phenomenon), then it indicates that the vision of the uncovered eye is very poor and should be checked at the hospital as soon as possible. Director Yu Gang reminds parents that early detection of amblyopia depends on the close cooperation of parents, kindergartens, schools and hospitals, and most importantly, parents themselves who spend time with their children. Common diseases causing amblyopia There are many causes of amblyopia, which are summarized as follows: pediatric strabismus, high hyperopia, myopia and astigmatism, congenital cataract, severe ptosis, and congenital optic center and optic nerve dysplasia. The prognosis for congenital and form-deprived amblyopia is poor. Refractive, strabismic, and refractive amblyopia have a better prognosis, and the key is early detection, timely and correct treatment. Can amblyopia be cured and at what age is the best treatment period? The factors that may affect the effect of amblyopia treatment are: family history (amblyopia or strabismus), infantile disease, type of amblyopia, original visual acuity at the time of onset, refraction, type and degree of strabismus, age of first diagnosis and nature of gaze, etc. It has been clinically proven that the original visual acuity of the amblyopic eye (the lighter the amblyopia, the higher the efficacy), so whether amblyopia can be cured is related to many of the above factors. Many parents think that amblyopia should be treated when the child is older, because the child will know better and the treatment will be easier to cooperate. This is because children’s visual function is unstable during their visual development, and they are prone to both amblyopia and normalization. Some studies have shown that the critical period is within 2 years of age and the sensitive period is before 6-8 years of age. The older the child is, the less time it takes to treat and the less effective it is, but we should not give up on treatment. The treatment of amblyopia is not an overnight thing, it is a constant battle, preschool children have more time to cooperate with the treatment, after school some treatment will be affected because of learning, which often brings difficulties to the treatment and affects the efficacy, which requires the long-term cooperation of parents and children and persistence.