The shape variation in the cornea causing it to be curved more in one direction than another is known as what?

• A. keratoconus
• B. astigmatism
• C. myopia
• D. hyperopia

Answer: (B)

Astigmatism occurs when the cornea has uneven curvature in different directions, so light rays don’t converge to a single point on the retina. Instead, they focus along two principal meridians, producing blurred or distorted vision at all distances. This directional curvature is what makes vision appear stretched or warped in one orientation.

Other conditions describe different problems: keratoconus involves thinning and a cone-shaped bulge of the cornea, not just a simple directional difference in curvature; myopia means distant objects blur because the eye focuses light in front of the retina; hyperopia means nearby objects are blurry because light focuses behind the retina. Astigmatism is corrected with lenses that have different powers in different meridians (toric lenses) or by reshaping the cornea.