DON’T LOSE SIGHT OF CLOUDY VISION!

What is a cataract?

A cataract is a clouding of the normally clear lens in the eye. For people who have cataracts, seeing through a cloudy lens is like looking through a fogged-up window. Cataracts are very common in older people.

What does the lens do?

The lens functions much like a camera, focusing light that enters the eye onto the retina at the back of the eye. Once it reaches the retina, light is changed into nerve signals that are sent via the optic nerve to the brain. The lens must be clear for the retina to receive a sharp image.

How do cataracts form?

As we age, the lens in the eyes becomes less flexible, less transparent and thicker. Tissues within the lens break down and clump together, clouding small areas within the lens. As the cataract continues to develop, the clouding becomes denser and involves a greater part of the lens, which begins to discolour to yellowish/brown. The cataract scatters the light as it passes through the lens, preventing a sharp image from reaching the retina, and resulting in blurred vision.

Cataracts may develop in only one eye, but they usually develop in both eyes, although they may not be totally symmetrical, and the cataract may be more advanced in one eye.

How do cataracts affect vision?

Most age-related cataracts develop gradually, so changes in vision may not be noticed at first. As the cataract grows larger and clouds more of the lens, you may become aware of some of the changes. These may include blurred or dim vision, increased difficulty with vision at night or in low light, sensitivity to light and glare, “halos” around lights, fading of colour vision, distorted vision, or double vision in one eye. You may find that your prescription for glasses or contact lenses changes more frequently.

How are cataracts diagnosed?

The only way to know for certain if you have cataracts is to have an eye examination, so make an appointment to see your optometrist if you notice changes in your vision. He or she may conduct several tests, including reading an eye chart with progressively smaller letters to determine your visual acuity or ability to see at various distances; inserting drops to dilate the pupils so that the retina and optic nerve can be examined; measuring the pressure inside your eyes; and other tests to assess the general health of your eyes.

What causes cataracts?

There are many causes of cataract, but it may be that the protein in the lens changes with wear and tear over the years. Some cataracts are related to inherited genetic disorders that cause other health problems and increase your risk of cataracts. Cataracts can also be caused by other eye conditions, medical conditions such as diabetes, trauma or past eye surgery.

The risk of cataracts increases with age, but there are other factors that increase this risk. They include smoking, excessive exposure to sunlight, family history of cataracts, high blood pressure, and prolonged use of corticosteroid medication.

How are cataracts treated?

In the early stages, vision can be improved with brighter lighting, stronger glasses and anti-glare sunglasses, but usually surgery is the only effective long-term treatment. Surgery involves removing the cloudy lens and replacing it with an artificial lens. If for any reason the lens cannot be replaced with an artificial lens, glasses or contact lenses can be prescribed and will be equally effective. Your optometrist will refer you to a specialist for the surgical procedure.

A cataract needs to be removed only when vision loss interferes with your everyday activities. You and your optometrist need to make an informed decision together. In most cases, delaying cataract surgery will not cause long-term damage to your eyes or make the surgery more complicated. You do not have to rush into surgery, but should have regular check-ups to monitor the progress of the cataracts.

Can I do anything to protect my vision?

There is no evidence to prove that cataracts can be prevented, but there are certain strategies that may be helpful. Have regular eye examinations, so that any problems can be detected in their early stages. Give up smoking. Ultraviolet light from the sun may contribute to the development of cataracts, so wear sunglasses that block ultraviolet B (UVB) rays when you're outdoors. Manage your general health as well as other medical conditions, such as diabetes. Choose a healthy diet that includes plenty of fruits and vegetables, which are rich in vitamins, minerals and antioxidants.