Do you have diabetes? If yes, then take care of your eyes. It’s because vision problems are one of the most significant complications caused by diabetes and is a common cause of blindness.
Poorly managed diabetes can affect the lens, macula, retina, and optic nerve in your eyes and may cause permanent blindness. This is why it’s important to understand how this condition may affect your eyes.
The most common and serious eye condition caused by diabetes is diabetic retinopathy. However, diabetes causes a number of other eye conditions as well.
How diabetes affects your vision?
Diabetes may affect your vision (in severe cases) and may not, but in any case, it will affect your eyes and the way it functions. This is especially when your blood sugar levels are uncontrollably high. Here’s how it affect your eyes:
- Any changes in your blood sugar levels have an impact on your lens. This may blur your vision and as such, you may face difficulty in your day-to-day activities, depending on the blood sugar levels. It’s not necessary that people with diabetes will develop an eye condition. It all depends on your sugar level.
- Diabetes also makes your eye lens cloudy. This condition is called cataract. This happens when your eye lens swells due to high levels of blood glucose in the fluid around your eye lens. As a result, the area around the lens has more water than usual and it cannot focus the light properly on the retina. People with diabetes stand at a higher risk of developing cataract at an earlier age than non-diabetic people.
- Diabetic people may also develop glaucoma, an eye condition that damages the optic nerve. Elevated blood sugar levels may raise the ocular pressure (pressure inside your eyes) and result in glaucoma.
- Diabetes can also affect the flow of blood in your eyes. It may cause blockage in the vessels obstructing the flow of blood to your retina. This blockage can also cause leakage or cause unnatural growth in the vessels. All these conditions cause different types of retinopathy. This condition can turn worse, depending on the severity of the changes in the eye blood vessels.
Eye condition caused by diabetes
The World Health Organisation identifies diabetes as a major cause of blindness all over the globe. It is estimated that by 2030, the number of people suffering from diabetic retinopathy (DR) will rise to 191.0 million and the number of people suffering from vision-threatening diabetic retinopathy including Proliferative and Non-proliferative DR, and Diabetic Macular Edema (DME) may rise to 56.3 million.
Source: http://onlinelibrary.wiley.com/doi/10.1111/ceo.12696/pdf
Here’s a brief overview of eye conditions caused by diabetes:
5. Diabetic Retinopathy
Diabetic Retinopathy is of several types, depending on the level at which the blood vessels in your eyes are affected. This includes:
- Background Diabetic Retinopathy
This type of retinopathy does not usually affect your eyesight. Your eyes develop this condition when there is a blockage in your capillaries in the retina. This causes the capillaries to swell which is known as microaneurisms.
A microaneurism may also leak blood or a fluid known as exudate. These changes in the eyes don’t affect the vision immediately but the eye doctor needs to monitor it regularly so that the condition doesn’t get worse.
- Proliferative diabetic retinopathy
The blood vessels in the retina help in delivering oxygen to your retina for its proper functioning. If background retinopathy gets worse, these blood vessels may get completely damaged. As a result, a large section of your retina is affected and the blood supply to the retina is reduced.
This condition is known as ischaemia where particular areas in your retina are deprived of the oxygen they require. Your body then tries to fix this issue by growing new blood vessels on the surface of the retina or the vitreous gel. However, these blood vessels are extremely weak and as such, they bleed causing haemorrhages.
Such haemorrhages can completely block your vision as your retinopathy enters a proliferative stage. In many cases, with time, the blood might get reabsorbed into your body and there is a chance for your vision to improve. But chances are high that these haemorrhages will keep resurfacing and the blood may not be absorbed completely.
This may lead to permanent vision loss. If the haemorrhages are large, it can also scar the tissue. As the retina shrinks, the scar tissues may distort the retina or pull it on. As a result, the retina may get detached and cause serious vision loss.
- Diabetic maculopathy and diabetic macular edema
When the retinopathy affects your macula, it causes Diabetic Maculopathy. This condition affects your central vision which is important for seeing colours and other fine detail.
As a result, it becomes difficult for you to carry on precision tasks such as writing, reading and seeing other detail. If the fluid leakage is near the macula, the accumulation of fluid can result in macular swelling. This condition is known as diabetic macular edema. This makes your eyesight blurred and distorted. Even the colours may appear washed out.
6. Cataract
It’s through the lens that your eyes focus on an image and see. This lens is usually clear and free of any debris. Now, when you have a cataract, the lens becomes cloudy. Anyone can develop this condition but diabetic people tend to get them earlier compared to non-diabetic.
Also, cataract in a diabetic eye worsens faster. If your eye lens is cloudy, it cannot focus on images as it should. Common symptoms of cataract include blurry vision and light sensitivity. Cataract can be removed by surgery. The doctor will remove the cloudy lens and replace it with an artificial lens.
If you are diabetic the odds of developing the eye condition depends completely on your blood glucose levels. The lens of your eyes derives nutrients from the aqueous humour. This is the front part of your eye which is filled with fluid. Aqueous humour supplies oxygen and glucose to your eyes. Glucose is essential for proper functioning of the cells.
However, if the glucose levels are uncontrolled, the sugar content in your aqueous humour also increases causing it to swell and affects the clarity of your vision. The lens also has an enzyme that helps in converting glucose into sorbitol. When sorbitol accumulates in the lens, it affects the lens cells and other naturally-occurring proteins. As a result, the lens becomes more opaque. This condition eventually results in cataract formation.
7. Glaucoma
The relationship between diabetes and open-angle glaucoma is subject to research. Diabetic people are more likely to develop glaucoma compared to non-diabetics. Diabetes is also associated with a rare type of glaucoma known as neovascular glaucoma.
In some cases of diabetic retinopathy, the blood vessels in the retina are destroyed and as a result, the retina develops abnormal blood vessels. Neovascular glaucoma develops when new blood vessels grow on your iris. This obstructs the flow of fluid in your eyes, raising the eye pressure. This condition is difficult to treat; however, laser surgery can help in reducing the proliferation of abnormal blood vessels on the iris and your retina.
The doctor may prescribe medication for treating open-angle glaucoma. This is the most common form of glaucoma. Medicines can be used to lower eye pressure, reduce the amount of fluid in your eyes, and speed up the drainage process. Open-angle glaucoma usually doesn’t cause any symptom unless it has progressed to an advanced stage. A comprehensive eye examination is the only way to determine whether you have open-angle glaucoma or not.
You may notice these symptoms:
• Headaches
• Halos around lights
• Blurred vision
• Eye aches or pain
• Vision loss
• Watery eyes
How to prevent diabetic eye condition?
If your blood sugar levels are under control, you won’t have any problems in your vision. Even if you have, they won’t be severe. And that is why visiting an eye specialist from time to time is essential. This is the only way to find out whether your eyes are affected or not. The doctor may do the following tests and screening:
8. Diabetic Eye Screening
With early intervention, most of the diabetes-related eye conditions can be treated. And a thorough eye screening is the best way to detect any abnormality caused by diabetes. A comprehensive screening is essential during early stages of diabetic eye conditions as they don’t have any primary symptoms (except cataract). By the time the symptoms become noticeable, the condition becomes worse and difficult to treat.
During diabetic eye screening, the doctor will put an eye drop for enlarging the pupils. It takes 15-20 minutes and during that time, your vision is temporarily blurred. After that, the doctor takes photographs of your retina. The camera won’t touch your eyes and there will be several flashes each time a photograph is taken.
The light is pretty bright and the eye drops may make your eyes a bit stingy. Depending on the type of eye drops used, the haziness of your vision may last from two to six hours. After the screening procedure, everything around you may feel a bit bright. Do not worry, your vision will get normal soon after some time.
9. Photocoagulation (Scatter and Focal) and Vitrectomy
Scatter and Focal photocoagulation and vitrectomy help in preventing blindness in most of the cases. The sooner your condition is diagnosed, higher the chances that the treatment will be successful. In photocoagulation, the eye doctor will use a laser beam for making small burns on your retina. These burns seal the blood vessels, preventing further growth and leakage.
In scatter photocoagulation, which is also known as pan-retinal photocoagulation, the eye specialist will make hundreds of such burns in dotted patterns. This procedure reduces your chances and risk of blindness caused by vitreous haemorrhage or retinal detachment. However, this procedure will only work if the detachment hasn’t progressed much and before bleeding has occurred. Scatter Photocoagulation is also used for treating certain kinds of glaucoma.
Focal photocoagulation is where the eye care specialist aims the laser exactly on the leaking blood vessels in the macula. This procedure won’t cure blurry vision caused by macular oedema but it can prevent the condition from getting worse.
In case the retina has already detached or excessive amount of blood has leaked into the eye, this procedure is of no help. The next option that you have is vitrectomy. This is a surgery for removing scar tissue and cloudy fluid from your eyes. In this case too, the earlier you opt for the operation, the more likely it is to be successful.
For treating macular edema, the doctor either goes for Focal Laser Therapy or using medications. Focal laser therapy slows the leakage of fluid whereas medications can be injected into the eye to slow the growth of new blood vessels and for reducing the leakage of fluid into the macula.
Who are at the risk of developing diabetic eye disease?
Your chances of retinopathy are high if you have diabetes for a longer period. This means, almost everyone with type 1 diabetes may eventually suffer from non-proliferative retinopathy.
And most of the people with type 2 diabetes are also at the risk of developing it. If you are diabetic and you have good control over your blood sugar levels and if they are close to normal then you are less likely to develop retinopathy.
Most people with non-proliferative retinopathy usually do not show any symptoms. And that’s the reason why you should have your eyes examined regularly by an eye care expert.
Get your eye health diagnosed at a leading eye hospital in Kolkata
Get in touch with experts for thorough eye check-up or for glaucoma treatment in Kolkata. Visit http://www.dishaeye.org appointment to book an appointment.