What is described as opacity changes affecting the lens?

Cataracts are characterized by opacity changes that affect the lens of the eye, leading to a decrease in transparency. This condition occurs when proteins within the lens become altered, resulting in cloudiness that can vary in severity. As the cataract progresses, it can significantly interfere with vision, causing symptoms such as blurriness, difficulty seeing in low light, and increased sensitivity to glare.

Lenticular sclerosis is a related condition that typically occurs with aging but is distinct from cataracts. It involves a hardening and slight clouding of the lens that does not impair vision to the extent that cataracts do. Corneal edema affects the cornea rather than the lens and involves swelling that can lead to fluid accumulation and opacity, impacting vision but is not related to lens opacity changes. Retinal detachment involves the separation of the retina from its underlying supportive tissue, presenting its own set of visual symptoms but does not involve changes in the lens itself.

Thus, cataracts are specifically defined by the clouding of the lens due to various factors, making it the correct answer to the question regarding opacity changes affecting the lens.