What is a cataract?

A cataract refers to the clouding of the lens of the eye, which typically occurs as a part of the aging process but can also result from other factors such as genetics, certain medications, and health conditions like diabetes. The lens, normally clear, becomes opaque, leading to a decrease in the quality of vision. This cloudiness can obstruct light from passing through the lens to the retina, which can result in blurred vision, difficulty seeing at night, sensitivity to light, and the appearance of halos around lights.

In contrast, other options describe different ocular conditions. Misalignment of the eyes refers to strabismus, which affects the coordination of eye movements but does not involve the lens. Retinal detachment is a serious condition where the retina separates from its supporting tissue, leading to vision loss, and it does not involve the lens either. A progressive increase in intraocular pressure describes glaucoma, a condition that can damage the optic nerve and lead to vision loss, but again, it is unrelated to cataracts. Understanding these distinctions is important for recognizing how cataracts specifically impact vision and how they differ from other eye disorders.