What is a Cataract?

  • The leading cause of reversible blindness in the world.
  • A partial or complete loss of transparency of the crystalline lens substance and its capsule.
  • When a cataract develops, the lens becomes opaque and prevents the light rays focusing on the retina.
  • The image that the retina receives becomes dull and fuzzy.

Sight and the normal eye

Sight is possible with the combination of a healthy eye and brain. Inside the eye, behind the cornea is the coloured part of the eye (iris) with the black hole in the centre (pupil). Behind this is a lens. Light rays pass through the transparent cornea through the pupil and are then focused through the lens onto the retina. In a normal eye, the lens is made of a clear, flexible gel surrounded by the transparent lens capsule. The lens adjusts its curvature to fine focus light rays onto the back of the eye (retina).