What condition is characterized by a progressive thinning and bulging of the cornea?

Keratoconus is a condition characterized by progressive thinning and bulging of the cornea, which leads to a cone-like shape. This distortive alteration in the cornea can significantly affect vision, resulting in irregular astigmatism and increased sensitivity to light. As keratoconus progresses, the cornea becomes more steeply conical, which complicates the task of focusing light onto the retina properly. This condition often develops during the teenage years and can progress into the 20s and 30s.

Other conditions listed, such as cataracts, astigmatism, and glaucoma, do not involve the progressive thinning and bulging of the cornea. Cataracts refer to clouding of the lens in the eye, impairing vision. Astigmatism is related to an irregular shape of the cornea or lens that leads to blurred vision, but it does not involve significant thinning or bulging. Glaucoma is associated with increased pressure in the eye that can damage the optic nerve, but again, it is not characterized by changes in the corneal structure like keratoconus is. Understanding the distinct characteristics of keratoconus helps in diagnosing and managing this eye condition effectively.