The causes of astigmatism can be divided into two main areas: first, astigmatism without other eye pathologies, which is usually congenital and is present at birth, so it is recommended that when a child is 3.5-4 years old and can recognize the visual acuity chart, he should have his first vision check and eye examination in his life to rule out various eye diseases and determine whether there is refractive error. Astigmatism can be caused by large astigmatism, and if left untreated, it can affect the child’s vision for the rest of his or her life; second, astigmatism caused by other combined eye pathologies, such as scarring caused by corneal trauma can lead to astigmatism, for example, pterygium, whose degenerated conjunctiva invades the cornea and creates a large astigmatism, causing vision loss, or a large eyelid swelling, which has a compressive effect on the eye. There is a compressive effect that causes deformation of the eye that can also cause astigmatism.