16 November 2009

Diabetes: blind to the dangers?

Diabetic retinopathy is a potentially blinding complication of diabetes that affects people whose diabetes isn't under control. Use World Diabetes Day to brush up on the facts.


The eyes are the windows to the soul. They're also one of the first organs to suffer the damaging and irreversible effects of diabetes.

This is the message that South African optometrists Chris Eksteen and Charl Laas hope to communicate on World Diabetes Day (14 November).

On Friday, they formed part of a team of professionals who performed eye examinations on residents of Robben Island, many of whom have type 2 diabetes. The screening tests, an initiative of the Jonga Trust, took place at the V&A Waterfront.

The experts' main concern was diabetic retinopathy, a potentially blinding complication of diabetes that damages the retina of the eyes and affects people whose diabetes isn't well controlled.

In doing the screening tests, they hoped to catch the eye disease early, before too much damage could be done. Eksteen, Laas and other volunteers also used the opportunity to screen for undiagnosed diabetes, as one of the first signs of the condition are changes of refraction in the lens of the eye.

Principal of the Robben Island Primary School, Thetha Sithole, is having his eyes tested. He was diagnosed with type 2 diabetes in March 2009.

What is diabetic retinopathy?
The retina is the light-sensitive tissue situated at the back of the eye. Its main function is to change the light that enters the eye into nerve signals, and then to send these signals to the brain. Without a retina, the eye cannot communicate with the brain, making vision impossible.

In people with diabetic retinopathy, blood vessels leak fluid and blood onto the retina and the macula, the part of the retina that enables us to see detail. This condition, in its advanced stages, leads to shortage of blood supply to the retina and, ultimately, to blindness.

Who is at risk?
In South Africa, approximately 1 in 5 people over the age of 35 has type 2 diabetes. Alarmingly, more than 50% of these people are unaware that they have the condition.

All type 1 and type 2 diabetics, as well as expectant mothers who are diabetic, risk developing diabetic retinopathy. However, if you control your diabetes, there's very little chance that it will occur.

Children can also be affected. Eksteen says, for example, that he recently formed part of a screening initiative of diabetic children under the age of 12. Of the 39 children tested, 13 had early diabetic retinopathy.

George Pheta (55), a horticulturalist on Robben Island, is being screened for diabetic retinopathy. He was diagnosed with diabetes three years ago.

There are no early warning signs of diabetic retinopathy. The only way to detect it is through annual eye examinations.

There are two treatment options for diabetic retinopathy, which are very effective in reducing vision loss. These are laser surgery and vitrectomy. The latter option involves the removal of the whole or part of the vitreous humour of the eye.


  • Make sure your diabetes is under control: take your medicine as prescribed and follow a healthy lifestyle.
  • Learn as much as you can about diabetic retinopathy, especially if you are diabetic.
  • Visit an eye-care practitioner every year for an eye examination. Research shows that an estimated 90% of diabetes-related blindness cases can be prevented through routine eye examinations. Plus, it's the only way you'll know that damage is occurring.
  • Wear protective sunglasses if you have diabetes. Variable-tint lenses, which are clear indoors and become sun-lens dark when exposed to UV light, are best. Ask your optometrist about a brand that blocks UV rays completely, since excessive UV can be particularly damaging to the diabetic eye. Never buy sunglasses from street vendors – you can't be sure that these sunglasses offer sufficient protection against the sun.

Want to know more about diabetes? Watch this video:

(Carine Visagie, Health24, November 2009)

Sources: National Eye Institute (NEI); Transitions Optical; liquidlingo Communications; Sapa PR

Read more:
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World Diabetes Day


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