What causes astigmatism?

Astigmatism is primarily caused by irregularities in the shape of the cornea or sometimes the lens of the eye. When the cornea is shaped more like a football than a basketball, it leads to differences in how light rays enter the eye, resulting in blurred or distorted vision. This can stem from hereditary factors where a predisposition to such an irregular shape is passed down, or injuries that alter the corneal structure, further contributing to the development of astigmatism.

While excessive screen time can contribute to eye strain and discomfort, it is not a direct cause of astigmatism. Similarly, infections that scar the retina can lead to other vision problems, but they are not linked specifically to astigmatism. The natural aging process can affect vision through other common conditions like presbyopia or cataracts but does not directly cause astigmatism in the same way that corneal irregularities do.