What are cataracts?
Cataracts are the major cause of blindness worldwide and in Nigeria, accounting for 51% and 43% of cases respectively. Cataracts are cloudy (opaque) areas that develop in the lens of the eye.
The lens mostly consists of water and protein. The protein is arranged in a way that ensures clarity of the lens. However, with age and other causes that will be discussed below, some of the proteins may clump together, making the lens cloudy. This worsens with age, because the lens discolours with age, acquiring a brownish tinge which affects colour vision. With time, the cataract keeps developing till it restricts the amount of light entering the eye.
How do we see?
When you look at an object, light from the object passes through the cornea, then to the lens, the aqueous humour (fluid inside the eye), till it hits the retina at the back of the eye.
The lens in the eye acts like the lens of a camera, helping you to focus the light entering the eye on the retina, especially on the macula. The macula is the part of the retina that is responsible for our central vision. It is densely packed with seeing cells called rods and cones.
Nerve signals pass from these cells down to the nerve fibres in the optic nerve, then to the brain, enabling us to see. To have clear vision, the lens must be clear.