Sunday April 27, 2014
BY DR CHIN PIK KEE
MANY people are not aware that diabetes mellitus can cause blindness.
Fortunately, this disastrous outcome is avoidable if the right care is taken. One simple preventive measure is for diabetics to take retinal photographs once a year so that their doctors can easily detect early warning signs of eye damage.
The Malaysian Society of Ophthalmology operates Eye Photo, a non-profit retinal photography service, using a high-resolution digital fundus camera donated by Bank Simpanan Nasional.
The service is a pilot project to make retinal photography easily accessible, particularly to those diabetic patients who have not been getting their retinas checked.
Diabetes causes vision loss by damaging the retina, an important nerve layer in the eye.
If you compare the eye to a film camera, the retina is like the photographic film – just as a camera cannot produce good photographs with spoilt film, the eye cannot see clearly with a damaged retina.
Retinal damage from diabetes, or diabetic retinopathy, does not give rise to any eyesight problems at first.
However, as the disease worsens, symptoms such as blurring, distortion and floaters will eventually appear.
Unfortunately, there is often serious damage to the retina by the time patients notice anything wrong with their vision.
A doctor can diagnose diabetic retinopathy by viewing the retina directly, or by reviewing photographs of the retina.
Bleeding, fatty deposits, abnormal blood vessels or scar tissue in the eye are indications of diabetic damage.
If abnormalities that are serious enough to threaten vision are observed, treatment should be given promptly.
Effective treatments for diabetic retinopathy include retinal laser photocoagulation, injections of medications and surgery, depending on the situation.
Successful treatment can stabilise – or at least, markedly slow down – retinal damage and prevent progression to blindness. Nevertheless, it cannot restore the retina to normal; it is hence, essential that treatment is given before serious retinal damage has already occurred.
As there are usually no symptoms at this stage, everyone with diabetes should have routine screening for diabetic retinopathy, instead of waiting until eyesight problems appear.
Screening for diabetic retinopathy can be done either by the primary doctor treating the diabetes or by an ophthalmologist (an eye specialist doctor).
However, it can sometimes be difficult for non-ophthalmologists to examine the retina as they do not have special eye-testing equipment. Retinal photography comes in useful here, as it allows the doctor to see the retina in photographs, instead of needing to look directly inside the patient’s eyes.
Retinal photographs are taken quickly and painlessly – in a flash, literally – using a fundus camera. Most eyes give good quality pictures, except when there are small pupils, corneal problems or cataracts.
Patients without eyesight symptoms are ideal candidates for diabetic retinopathy screening using retinal photography. Others, who have already noticed vision problems, should best see an ophthalmologist for a complete eye check instead.
The Eye Photo project is strictly a photography service, and patients are responsible for bringing the photographs back to their doctors to look for signs of diabetic retinopathy. If the doctor sees any danger signs, the patient should be referred to an ophthalmologist.
Otherwise, the doctor can continue to monitor the patient with another retinal photograph after a suitable interval.
You can protect your eyes, kidneys and other important organs from diabetic damage by maintaining excellent diabetic control, normal blood pressure and optimal cholesterol levels, and by avoiding smoking completely.
Remember, preserving your vision starts with an eye examination – please get your retinas checked once a year even if you do not notice any problems with your eyesight.
http://www.thestar.com.my/Lifestyle/Health/2014/04/27/Photographing-retinas/
