What is a cataract?

A cataract is a white film covering the eye's lens, preventing light from seeping through. Cataracts form when protein in the eye’s lens accumulates in a clump of white, dense matter, which prevents the transfer of light to the retina. Sight works when the retina converts light from the lens into signals that are transferred to the optic nerve and sent to the brain to process clear visuals.

Why do cataracts occur?

Cataracts develop due to the release of oxidants in excess. Oxidants are oxygen particles that are chemically altered as a result of our lifestyle. Additional risk factors include cigarette smoke, exposure to ultraviolet radiation, the use of certain steroids and medicines, diabetes, trauma and treatment like radiation therapy.

Cataracts are classified according to where they develop in the eye. A nuclear cataract affects the eye’s centre, causing the nucleus to turn yellow or brown. Cataracts can develop around the nucleus and are wedge-like in shape, called cortical cataracts. Cataracts can also form behind the eye’s lens, which we term “posterior cataracts”. The formation of cataracts can occur due to congenital abnormalities, a secondary illness such as diabetes and the use of a steroid such as prednisone.

How do I look out for cataracts?

The obvious signs of cataracts include:

  • Hazy/cloudy vision
  • Difficulty seeing, especially at night
  • Faded colours
  • Sensitivity to light
  • Halos
  • Seeing double

What is cataract surgery?

Cataract surgery is a delicate way of replacing the damaged eye lens with a healthy, synthetic one in an inpatient setting. There are two ways of doing this:

  1. The first is done by breaking apart the cataract (phacoemulsification) to remove it piece by piece. First, doctors make a superficial cut in the cornea where a probe (a thin needle-like device) is inserted. The probe is an ultrasound device that emits waves to break apart the cataract into pieces. Next, the remnants are suctioned, and the artificial lens is placed to rest inside the natural capsule.
  2. Extracapsular cataract removal is the surgical extraction of the cataract in one go through a larger cut over the eye. Doctors work to remove the front capsule and the fogged-up lens that contains the cataract using surgical instruments. The capsule at the back remains in place for the artificial lens to rest.

What is the prognosis?

After surgery, you can expect your eyesight to improve over the next few days. You will notice the colours of objects to be much brighter because the new lens will be much clearer.

After surgery, you usually return to your eye doctor within a day or two, then a week after, and then again in a month’s time to monitor your progress and healing. An eye patch will prevent you from touching or rubbing your eye.



Do I need an eye patch after cataract surgery?

Your doctor may recommend you wear an eye patch after cataract surgery and a protective shield while sleeping at night until you recover completely.

Is it painful to remove cataracts?

Cataract surgery is not at all painful. Patients are awake during surgery. However, there is minimal discomfort present. Doctors administer a mild sedative to help keep you calm. Eye drops are also administered to numb sensation in the area. The eye may also be numbed with a local injection.

Can cataracts make a return?

Cataracts are unlikely to make a comeback. This is because synthetic lenses are unable to form cataracts. However, a thin layer of cells may form within the remaining capsule. This can be cleaned using a YAG laser in the clinic.

Dr Philip and Dr Precious Phatudi
are skilled ophthalmologists based in Sandton