The Crystalline Lens

We are born with a lens our eyes called the crystalline lens. The crystalline lens focusses light onto the retina, and it changes shape to allow us to focus between near and far objects.

As we get older, the lens grows bigger and changes in its optical properties. One of the first changes is that it loses the ability to change shape. This happens between forty and fifty years of age and leads to a reduced ability to see near objects.

Age Related Cataracts

As we get to our 70’s, the lens usually starts to become cloudy. This cloudyness is called a cataract. At the early stages people with cataracts will notice that they are more glare sensitive, have more trouble driving at night, and find low contrast objects such as peoples’ faces difficult to see at a distance.

As cataracts develop, vision becomes worse even with glasses, and glasses cannot be made to give good vision. This is because the lens inside the eye is cloudy. It is like trying to see through foggy glasses. As the cataracts get worse, the glasses prescription changes more quickly.

In most cases cataracts are a part of ageing, and we can all expect to get cataracts as we get older.

Some people get cataracts in their fifties, and some get them in their nineties.

Non-Age Related Cataracts

There are cases where cataracts are not caused by age. Cataracts can also be caused by:

  • certain medications, especially extended use of high doses steroidal medication
  • certain kinds of eye surgery or eye injury
  • other eye diseases
  • congenital cataracts which are present at birth
  • diabetes
  • some genetic conditions

Treatment for Cataracts

Treatment for cataracts involves surgery to remove the cloudy crystalline lens and replace it with a new plastic lens. This surgery is very developed and has few complications these days. Cataract surgery is performed by ophthalmologists – eye specialists.

During the eye examination the optometrist looks at the crystalline lens to assess if there are cataracts present and how significantly they affect vision. Once the cataracts are ready for surgery then the optometrist will refer the patient to an ophthalmologist for cataract surgery.