What is a cataract?

A cataract is defined as an opacification of the crystalline lens of the eye. This condition occurs when the normally clear lens becomes cloudy or opaque, which can lead to blurred vision and other visual disturbances. The crystalline lens is responsible for focusing light onto the retina, so any clouding can significantly impact visual clarity.

Cataracts can develop as a result of aging, injury, or other factors, and are commonly associated with numerous visual impairments. Treatment typically involves surgical intervention to remove the cloudy lens and replace it with an artificial lens. Understanding the nature of cataracts as an opacification is fundamental in ophthalmology, as it affects how patients will experience vision changes and informs treatment approaches.

The other options, which refer to conditions such as thickening of the cornea, issues with the optic nerve, or eye infections, are not related to cataracts and involve entirely different aspects of ocular health.