She adjusted them, noting how they changed the opacity of the lenses, and smiled to herself.

This procedure thus reduces the opacity of the lens of the eye.

Cataracts are opacities of the lens.

Juvenile cataracts: A congenital opacity of the lens of the eye due to abnormal early degeneration of the lens tissue.

The most common alteration in NF II is the juvenile subcapsular cataract (opacity of the lens) in young people.