There are about 422,000,000 million people living with diabetes worldwide, according to 2014 statistics by World Health Organisation (WHO).
The number of people living with diabetes goes up by the day, and is higher in developing countries, like Rwanda.
People with diabetes can have an eye disease called diabetic retinopathy. Chronically high blood sugar from diabetes is associated with damage to the tiny blood vessels in the retina, leading to diabetic retinopathy.
Diabetic retinopathy can cause blood vessels in the retina to leak fluid or haemorrhage (bleed), distorting vision. In its most advanced stage, new abnormal blood vessels proliferate (increase in number) on the surface of the retina, which can lead to scarring and cell loss in the retina.
In developed countries, diabetic retinopathy is the leading cause of vision impairment and blindness among working-age adults.
Dr Francis Mutangana, a senior consultant ophthalmologist at Oshen-King Faisal Hospital in Kigali, says diabetes affects many parts of the body including the kidney, heart, nerves, brain and eyes.
A study done by Mutangana a few years back on diabetic patients in Rwanda, showed that approximately 30 per cent of diabetic patients suffered diabetic retinopathy.
HOW IT COMES ABOUT
Dr Mutangana explains that this is a disease that affects the blood vessels found at the back of the eye.
“Whatever we see, the retina picks the message and takes it to the brain, once the eye sees something; the light goes to the back of the eye and it’s picked from there and then the nerves take it to the brain,” he says.
He says if one has a problem in this particular part of the eye, they may not be able to recognise what they see.
What happens with someone who has diabetes, he says, is that they have high blood sugar, and when one has the condition for a long time, it starts damaging the blood vessels in the retina.
“The persistently elevated blood sugars will start damaging the vessels. Initially, the vessels will swell and as the damage continues, they start leaking, making the watery part of the blood and proteins leak out and go into this membrane (retina),” he says.
Later, Dr Mutangana says, the swelling on the vessels will burst and bleed when the damage continues. When the bleeding happens, it can go into the part of the eye filled with a jelly-like substance and once it mixes with the blood, one is not able to see.
Another way the retina can be damaged, he explains, is that as the vessels burst, the remaining parts of the retina are not supplied by blood (they become hypoxic), and because the retina requires oxygen to function, new easily breakable blood vessels will grow, which in turn break, causing increased bleeding.
He says that this process is something that grows gradually and by the time one realises it, a lot of damage has already happened to the eye.
The problem with the condition, Dr Mutangana says, is that initially, people will not feel anything and are able to see well.
When it gets advanced, that is when they start noticing blurred vision.
The most important thing to do, he says, once a patient is diagnosed with diabetes, is to see an ophthalmologist immediately and further follow-ups are decided based on the findings.
This typically ranges from six months to one year for the mild cases.
Dr Mutangana says this is helpful because one is screened to find out if the condition is there, and if it is — and in its early stage — treatment is not as complicated.
“The big challenge we are facing is that we normally see such patients very late, but once they come for screening; such cases can be avoided. If they are screened and found to have problems, appointments can be made depending on how serious the problem is,” he says.
He says that patients with diabetes tend to seek treatment for blood sugar handling only, yet it’s also necessary to have their eyes and other body organs, like the kidneys and heart, checked as well.
Although diabetes as a disease can’t be cured, when such patients come for eye check-ups and are found to have diabetic retinopathy, the progression of the condition can be stopped.
Dr Mutangana explains that normally when patients come for treatment, some drops are put in the eye which helps it open, allowing the specialist to look inside and identify the part that is affected, and if it’s mild, moderate or at a late stage.
“In its early stage, the patient is advised on what to do, unlike at an advanced stage where treatment will be needed urgently,” he says.
In the past, Dr Mutangana says there was no treatment for the condition, but with technology, laser treatment is used, especially to burn the areas in the eye that are affected. This, however, is only helpful if one is diagnosed in time.
The lasers have to be combined with good control of blood sugar, cholesterol and blood pressure for the treatment to be effective.
There are some eye injections that can also be given if someone has diabetic macular edema, another cause of reduced vision in diabetic retinopathy, to take away the fluid and reduce swelling in this part of the eye.
Oshen-King Faisal Hospital is one of the few centres in the country that offers treatment for this condition, and soon, they are going to start surgical treatment for advanced cases of the disease as well.