What does the term "astigmatism" refer to?

The term "astigmatism" refers to an irregular curvature of the cornea or lens, which results in blurred or distorted vision. In a healthy eye, the cornea and lens should have a smooth, spherical shape to focus light evenly onto the retina. However, in individuals with astigmatism, the cornea or lens may be more steeply curved in one direction than the other, resulting in two focal points instead of one. This anisotropic shape leads to images appearing out of focus or distorted, regardless of the distance at which they are viewed.

Understanding this condition is essential for effective diagnosis and treatment, as it can be corrected with glasses, contact lenses, or refractive surgery. The other options, while related to eye health, do not accurately describe the specific nature of astigmatism. Age-related vision conditions pertain to changes that occur as one ages, eye infections involve microbial agents affecting the eye, and eye misalignment refers to strabismus, which is unrelated to the curvature issues characteristic of astigmatism.