SHARES
Dr Cheng Jin Fong, ophthalmologist at The Radiant Eye Centre
Diabetic eye disease is when diabetes affects the function of the eye, causing damage to the eyes and over time, may result in poor vision or even blindness. We consult Dr Cheng Jin Fong, ophthalmologist at The Radiant Eye Centre, as she shares the various ways diabetes can affect our eyes and what we can do to protect our vision.
GetDoc: How often do you see diabetic patients for eye conditions?
Dr Cheng: I see diabetic patients in my clinic almost every day. That’s how common diabetes is among the population. I see them for eye screenings or if diabetes affects the eyes. I see patients who happen to have diabetes for other eye conditions as well.
GetDoc: How does diabetes affect the eyes?
Dr Cheng: How the eye works is that the lens focuses all the light on the retina, which is a thin layer of membrane with all the light-sensitive cells on it. When the retina receives messages of the images, it sends messages through the nerves into the brain. You can see that the retina is an essential function of the eye, and diabetes largely affects the retina.
Therefore, there are four things we look out for in patients with diabetes: diabetic retinopathy, diabetic maculopathy, cataracts, and glaucoma.
The blood vessels at the back of the eye can affect what we call diabetic retinopathy. What diabetes does is that it causes the blood vessels to leak and bleed. The eye is the only place in the body where you can visualise the blood vessels. The changes that we see are the changes from the leaking blood vessels. We can either see blood in the eye where there isn’t supposed to be blood, proteins, or even fat leaking out of the blood vessels. These protein leaks can cause either white or yellow spots on the retina.
Similarly, on the retina is the centre of our vision, an area we call the macular. What can happen in the macular is swelling due to insufficient blood supply. The macular is an area where there are no blood vessels but has the highest metabolic rate, which means it needs the most energy. So, if there are insufficient nutrients supplied to the macular because the blood vessels are not functioning properly, then the macular can swell and cause issues to the vision. Macular swelling is also called macular edema. Therefore, the blood vessels at the edges being blocked and the macular in the centre being swollen are the two areas the retina can get affected by diabetes.
Diabetes can also affect the lens, causing cataracts. It can also give you glaucoma due to increased pressure. High pressure can press on the nerves and cause damage to the vision.
People without diabetes can also be affected by these eye conditions. Take cataracts for instance. Every single person will develop cataracts if they live long enough. However, frequently among diabetic patients, cataracts tend to develop earlier than expected. Especially among patients who have poor sugar control, the cataract can swell up from the increased sugar. Yet, swelling can also decrease with better sugar control. Thus, the patients’ conditions can be very unstable. By and large, diabetic patients will often develop cataracts earlier than non-diabetic patients.
GetDoc: What are the major consequences of diabetic eye conditions?
Dr Cheng: The biggest problem is decreased vision. Also, if the blood vessels are affected, it can cause bleeding in the retina itself and in the vitreous jelly in the centre of the eye. That is what we call vitreous haemorrhage. When that bleeding occurs, again it can affect vision.
What can happen after that is scarring. The scarring of the retina can cause the retina to get detached and pulled off. This is called retina detachment. If a patient develops retina detachment, they can become blind.
GetDoc: What kind of treatment options for diabetic eye conditions do you offer?
Dr Cheng: My firm belief is that prevention is better than cure. Therefore, first and foremost, screening is the most important for diabetic patients. For both insulin-dependent and insulin-independent diabetics, yearly eye screening is recommended even if they might not show any symptoms.
Regardless of any changes in eye conditions, the best way to manage your health is through diet control. As mentioned, diabetes affects the blood vessels which we can see in the eyes. However, diabetes also affects other parts of the body, including the kidneys, brain, and heart. Hence, if health changes caused by diabetes are bad in the eyes, they will definitely be bad everywhere else in the body. Therefore, the most important thing is still diabetes control to keep your glucose levels low, such as medication, diet management, and exercise.
We also have treatment options for when the diabetic eye disease becomes severe: laser treatments, injections, and surgery. We always share the benefits and risks of every treatment option with the patients so that they can make a decision.
In the past, we used to perform a lot of laser treatments. Lasers are used to burn away tissues at the edges of the retina to preserve the blood supply for the centre area of the vision. Lasers are also used for the centre of the vision to reduce swelling in that area so that vision can return.
These days, however, with the advent of anti-vascular endothelial growth factor (anti-VEGF) injections into the eye, we have reduced our dependency on laser treatments. Furthermore, we have noticed better results with anti-VEGF than with laser treatments.
We tend to leave surgery as the very last option. For instance, we will consider surgery if patients have retina detachment and are going to be blind. Hopefully one day, surgery will become a thing of the past due to medical advancements and greater awareness among diabetics. There are also low vision aids available such as magnifiers, brighter lighting, special glasses. If vision is very bad, walking canes and guide dogs are also things we can do to help those with poor vision.
After that, it is a matter of maintenance. Diabetes is a disease that never goes away. Oftentimes, we hope that the blood sugar can be maintained so that good vision can be preserved. However, for patients who have poor blood sugar control, the disease can progress. There have been patients who have become blind due to diabetic retinopathy, or who come to us in very late stages of their eye disease, by which time they will end up with poor vision. This is why we emphasise annual screening, especially if you have diabetes.
GetDoc: What is the frequency of follow-up?
Dr Cheng: The more severe the disease, the higher frequency for follow-ups. Once patients develop diabetic eye disease, I see them about once every four months just to ensure that their eye disease does not develop too rapidly.
In recent times, patients are more aware of their disease and have better diabetes control, which is a good thing. The eye diseases tend to be detected earlier and are milder as well. Awareness is definitely important. Additionally, if patients have frequent screening and have treatments instituted earlier, they tend to avoid going down the route of a severe diabetic bleed, scarring, and retina detachment.
Diabetic eye disease is a common occurrence and can be extremely dangerous especially without proper diabetic management or regular screening. Schedule an eye screening session with Dr Cheng on GetDoc today.
by waiyee
Film junkie. Matcha drinker. Dog lady. Will write for food. View all articles by waiyee.
