What is the relationship between myopia and astigmatism?

Why do myopia have astigmatism?

In the process of myopia correction, many people will find through examination that myopia is not the only problem, and most people with myopia will be accompanied by a certain degree of astigmatism.

So why do most of them have astigmatism?

What is astigmatism?

Astigmatism is when the cornea or lens of the refractive surface of the eyeball is spherical astigmatism, the refractive power of each meridian or each part is unequal, so that the parallel light entering the eye does not form a complete focus on the retina, but becomes two focal line.

The relationship between myopia and astigmatism

In fact, the difference between myopia and astigmatism is very simple.

Nearsightedness means that it is clearer when seen near, but not clear when seen far away, but astigmatism is when the edges of objects are blurred.

Severe astigmatism can even lead to double images, making it difficult to see clearly regardless of distance.

In the development of the two, the change of astigmatism is relatively stable and slow compared with myopia.