What is a Cataract?

A cataract occurs when the lens of the eye becomes clouded or opaque. The lens of the eye is similar to the lens of a camera. It is located directly behind the pupil and its function is to focus the incoming light rays onto the retina at the back of the eye.

The images are then transmitted from the retina to the brain as electrical impulses via the optic nerve. When a cataract occurs, light is unable to pass through the lens and so vision becomes blurred, much as looking through a dirty window.

What causes cataracts

Most commonly, cataracts are caused by the deterioration of the normal protein structure within the lens of the eye as a person ages.

The vast majority of people who have cataracts are healthy with no other eye diseases.

However, cataracts can be secondary in the presence of medical conditions such as diabetes; the use of certain drugs and radiation damage; severe glaucoma or eye injuries. Cataracts can occasionally occur in infants and young children as a congenital defect.

What are the Symptoms?

Cataracts may develop rapidly over a few months or slowly over several years. Most often the second eye will be affected but not necessarily at the same time or rate.

As your cataract progresses, you will notice a deterioration of your distance and reading vision. You may also experience sensitivity to light or glare intolerance, especially at night. All of these symptoms are normal and are no cause for alarm. Altering your glasses may help in the early stages.

However, changing the strength of your glasses will eventually be insufficient. Surgery then becomes necessary.

Concerns and Expectations

Post-operatively, you can expect a change in your refraction. This may affect your uncorrected vision and spectacle lens power.

Occasionally, unpredicted variations can occur resulting in significant changes in spectacle power.

Please ask your doctor about your likely visual results both with and without spectacles following your surgery.

Many patients experience black spots or floaters in their vision after surgery.

These are usually not significant, however mention them to your doctor on your next visit should you experience them.

  • Haloes, glare and distortion of lights occur frequently. These dissipate with time.
  • Colours are brighter and contrast is enhanced. You may find that you are more sensitive to sunlight. This is normal. Wearing good quality sunglasses will help.
  • Some people notice grittiness as the wound heals. This resolves with time. In approximately one-third of patients, the posterior capsule thickens with time causing clouding and reduction of vision. This requires treatment by YAG laser. The procedure is non-painful and gives an immediate improvement in vision. It is performed in the consulting rooms at a routine consultation.

Articles on Cataracts