What condition affects the shape of the cornea, causing both near and far objects to be out of focus?

Astigmatism is a refractive error caused by an irregular curvature of the cornea or lens of the eye. In a healthy eye, the cornea is evenly curved, allowing light to focus sharply on the retina for clear vision. However, with astigmatism, the cornea has a more oval shape, leading to multiple focal points and causing distortion or blurriness for both near and distant objects. This refractive error can impact daily activities such as reading and driving, where clear vision at varying distances is necessary.

In contrast, myopia (nearsightedness) affects distance vision, causing difficulty seeing far away. Hypertropia (more commonly known as hyperopia or farsightedness) impacts nearby vision, making it hard to see close objects clearly. A cataract, which is the clouding of the eye's lens, can also cause vision problems but does not specifically alter the cornea's shape like astigmatism does. Thus, astigmatism is the condition that directly affects corneal curvature and results in out-of-focus vision for both near and far objects.