About Diabetes
Diabetes is becoming the epidemic of the 21st century. Diabetics represent 3% of the population worldwide and are set to increase to 4.4% by 2030. The reasons for this increase mostly relate to changing diet and sedentary lifestyles but genetic factors play a role as well. The number of young insulin dependent diabetics remains about the same – approx 1% of the population – but it is the increase in diabetes in middle and advancing age which is becoming much more frequent. Approximately 1.5 million Australians know they have the condition and another 500,000 are not yet aware that they have or will develop the condition. 85-90% of all diabetics are Type II who do not require insulin initially, and can manage with diet and or diet and medications.
Diabetes affects the eye due to changes in the small blood vessels in the retina. The retina is like the film in the back of an old camera. The blood vessels become a little leaky and the blood cells block up the small capillaries. Initially these effects are not serious, however, after a longer period of time the combination of blockage and leakage cause damage to the retinal cells, resulting in loss of vision. In advanced stages this whole process leads to the formation of new friable blood vessels in the eye; these can bleed and lead to sight loss. If you get screened regularly this complication is fortunately rare.
This picture shows severe maculopathy with leakage from blood vessels, haemorrhages and swelling of the retinal tissues – it will be a challenge to recover vision this late.
Prevention and Screening
Part of the problem with a disease that initially is not causing an obvious problem is that we tend to ignore it. Think proactively and get into good habits early – this will pay dividends in the future.
The following interventions reduce the likelihood of you developing retinal (visual) complications of diabetes:
- Good diabetic control – this means recording your blood sugars regularly and getting glucose levels down to normal levels. You need to attend your GP and Diabetic nurse regularly, so they can intervene when things start to get out of control. You need to actively take part and become empowered in this process, as it will motivate you towards better control.
- Stop smoking – sadly smoking diabetics rarely make it into old age.
- Lose weight and exercise – this will reduce your glucose levels and may even stop you requiring medications. You may need the help of a dietician for this.
- Blood pressure needs to be controlled.
- Cholesterol and lipid (blood fat) levels need to be controlled.
- See a dietician, understand the do’s and don’ts in relation to your diet.
- As an Ophthalmologist, my preference is to have involvement in the screening of all diabetics, and not to leave this to any other health care professionaIs, as I firmly believe that this leads to the best outcomes.
Referral to see me for diabetic screening can be made in writing from your GP or Optometrist.
Once you have come to see me I will assess your eyes with the pupils dilated. This means that your vision will be blurry for several hours, hence you will need to bring a driver.
I will inform you of what is going on and recommend a review date. Generally these are yearly, initially.
Investigations may include:
- Blood glucose level tests (HbA1C)
- Blood test for lipids/cholesterol
- Fundus photography (Back of the eye pics)
- Fluorescein angiography
- OCT scan
How do I manage retinopathy of it occurs?
If you start to develop areas of leakage, a scan will be performed (OCT scan and sometimes fluorescein angiography) which will assess the degree of blockage and leakage.
Areas that need treating will sometimes need small laser spots applied to the retina to seal the leaking areas off. Laser is a very bright light of one wavelength, which causes a thermal change in the retina leading to prevention of leakage. This is generally painless and well tolerated. Local anaesthetic drops minimize the discomfort felt.
On the left you can see new vessels growing and on the right these have bled leading to sight loss. The vitreous jelly will need to be removed and the back of the eye lasered.
Sometimes the areas of leakage are less well controlled and a series of injections is required. This sounds scary but in fact is very well tolerated.
On the left the vitreous jelly has been removed and the retina has been lasered – this will prevent
further new vessels from forming and bleeding. On the right there are fibrous membranes pulling the retina away from the back of the eye. This requires painstaking surgery to peel away the fibrous tissue in order to save some useful sight.
If there is more of an issue than leakage, new friable blood vessels will form. By treating large areas of retina with laser these vessels can be made to regress, thus reducing the risk of bleeding and loss of vision.
Sometimes surgery is required to remove blood from the eye and repair the retina if there have been extensive areas of damage.
Banner image: An angiogram of a diabetic with heavy laser treatment.
Useful links:
http://www.diabetesaustralia.com.au
http://www.nei.nih.gov/health/diabetic/retinopathy.asp
http://www.diabetes.org.uk
http://www.rcophth.ac.uk/page.asp?section=365§ionTitle=Information+Booklets
