Astigmatism of 400 degrees is a high degree of astigmatism, which can have a significant impact on naked eye vision, especially in children, whose eyes are not yet fully developed. 400 degrees of astigmatism can be seen in two conditions: first, pathological astigmatism, which can be seen in the cone cornea, which needs to be treated early once detected and can be improved with corneal contact lenses in the early stages of the disease. In the early stages of the disease, corneal contact lenses can be used to improve vision. When the shape of the cone cornea becomes more pronounced, surgery may be required to avoid corneal rupture. Secondly, if the astigmatism is physiological, this condition can be promptly examined and fitted with frame glasses or corneal contact lenses, and physiological astigmatism, as the child grows older, usually does not change, but also does not become smaller. Therefore, if the child has 400 degrees of astigmatism, he or she must go to a regular hospital to improve the vision examination, optometry, corneal topography, corneal thickness, etc. to clarify the specific situation.