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When you think of diabetes, you probably think of glucose. Insulin. High blood pressure. Your pancreas.

But what about your eyes? Although they may not be the first thing you think of when it comes to diabetes, your vision can be heavily impacted and permanently damaged by it, with one in three people aged 40 or older with diabetes showing signs of diabetic retinopathy, according to the US National Institute of Diabetes and Digestive and Kidney Disease. Often, there aren’t clear early warning signs that diabetic eye disease is developing or even progressing. The longer you have diabetes, the greater the risk you have of it affecting your eyes.

Dr Diljeet Kaur Gahir

Dr Diljeet Kaur Gahir, Specialist Ophthalmologist, Prime Hospital and Medical Centre

“According to the American Academy of Ophthalmology, people diagnosed with diabetes should have a prompt screening at the time of diagnosis and at least yearly screenings thereafter,” says Dr Diljeet Kaur Gahir, Specialist Ophthalmologist, Prime Hospital and Medical Centre. “Women with diabetes who become pregnant should be examined early and closely in the course of the pregnancy because the disease can progress rapidly. Screening frequency also depends on the age of the patient, the stage of the disease, metabolic control of blood sugars, and systemic comorbidities. Screening frequency could vary to aid treatment plans of treating endocrinologists and nephrologists.”

Dr Emad Mahmoud Badawy, Specialist, Department of Ophthalmology at Medcare Eye Centre, Shaikh Zayed Road in Dubai, says after the usual routine eye examination such as vision, refraction, intraocular pressure and examination of the front part of the eye, detailed examinations of back part of the eye such as dilated fundus exam, optical coherence tomography and fluorescein angiography should be done.

“Diabetic retinopathy is best diagnosed with a comprehensive dilated fundus exam,” says Dr Badawy. “For this, drops placed in your eyes widen (dilate) your pupils to allow your doctor a better view inside your eyes. During the exam, your eye doctor will look for abnormalities in the retina (back part of the eye).”

Dr Emad Mahmoud Badawy

Dr Emad Mahmoud Badawy, Specialist, Department of Ophthalmology at Medcare Eye Centre

The optical coherence tomography (OCT) includes pictures to provide cross-sectional images of the retina that show its thickness. This will help determine how much fluid, if any, has leaked into retinal tissue. “Later, OCT exams can be used to monitor how treatment is working,” adds Dr Badawy.

“In fluorescein angiography, after your eyes are dilated, a dye is injected into a vein in your arm. Then pictures are taken as the dye circulates through your eyes blood vessels. The images can pinpoint blood vessels that are closed, broken or leaking. Depending on the stage of diabetic retinopathy your doctor will decide the follow-up intervals, which is usually every three to six months according to the eye condition and the treatment options.”

Dr Chidamber B. Srinivas, Specialist Ophthalmology, JTS Medical Centre, explains that eye issues are detected when one looks at the pathogenesis of diabetic retinopathy, which is damage to the vessel wall due to hyperglycaemia, basement membrane thickening, pericyte loss, microaneurysms, IRMA (intra retinal microaneurysms) and preretinal neovascularization, which can eventually lead to blindness through haemorrhage and tractional retinal detachment.

Dr Chidamber B. Srinivas

Dr Chidamber B. Srinivas, Specialist Ophthalmology, JTS Medical Centre

“For the vascular changes to start it takes time,” says Dr Srinivas. “The central vision in many cases may not be involved and changes could be taking place in the peripheral retina. When the central macula is involved, this is when the patient becomes aware of the symptoms and vision problems. When there are no retinopathy changes and no symptoms and control is well maintained, then an exam once a year is enough. If it is mild retinopathy, then once in three months and if severe then monthly or even closer follow-ups may be needed.”

The condition can develop in anyone who has type 1 or type 2 diabetes. The longer you have diabetes and the less controlled your blood sugar is, the more likely you are to develop this eye complication. In both cases the visual symptoms of diabetic retinopathy are the same - spots or dark strings floating in your vision (floaters), blurred vision, fluctuating vision, dark or empty areas in your vision and vision loss.

“What influences and allows these to manifest is the duration and the quality of sugar control,” explains Dr Srinivas. “Although retinopathy usually does not appear for about five years after a type 1 diabetes diagnosis, it may already be present when type 2 diabetes is diagnosed. After 15 years of having diabetes, 98 per cent of those with type 1 diabetes and 78 per cent of those with type 2 have some degree of retinal damage.”

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Treatment and care

If left untreated, diabetic retinopathy could cause irreversible vision loss. Luckily, there are treatment options available for the condition. According to Dr Dheeraj Kewlani, Specialist Ophthalmologist, Aster Clinic, Bur Dubai, the treatment is the same whether the patient is type 1 or type 2 but in general, type 1 patients require earlier treatment and the condition is more severe than in type 2 patients. “The treatment requires multiple approach that is diet control, exercise, oral hypoglycaemic tablets, and insulin injection,” says Dr Kewlani. “Treatment may include eye drops, laser to retina and injections in the eye. If the retinopathy is advanced then the person may require eye surgery as well, so timely detection and treatment is important so that it is checked at the early stages and not allowed to progress to advanced stages where there is a possibility of even losing vision.”

Therapy options have changed over the years and the treatment depends on the severity. The aim is to slow or stop the progression. Early diabetic retinopathy, mild or moderate non-proliferative diabetic retinopathy might not need treatment right away. However, your eye doctor will closely monitor your eyes to determine when you might need treatment, while the endocrinologist will determine if there are ways to improve your diabetes management. “When diabetic retinopathy is mild or moderate, good blood sugar control can usually slow the progression,” says Dr Badawy.

Dr Dheeraj Kewlani

Dr Dheeraj Kewlani, Specialist Ophthalmologist, Aster Clinic, Bur Dubai

Advanced diabetic retinopathy or proliferative diabetic retinopathy or macular edema needs prompt treatment. Depending on the specific problems with the retina, options include injecting medications called vascular endothelial growth factor inhibitors into the vitreous of the eye. “They help to stop the growth of new blood vessels and decrease fluid build-up,” says Dr Badawy. “These drugs are injected using topical anaesthesia and can cause mild discomfort, such as burning, tearing or pain for about 24 hours.”

In some cases, the injection is used with photocoagulation, a laser treatment also known as focal laser treatment and can stop or slow the leakage of blood and fluid in the eye. During the procedure, leaks from abnormal blood vessels are treated with laser burns.

There is another treatment called anretinal photocoagulation, also known as scatter laser treatment, that can shrink the abnormal blood vessels.

“During the procedure, the areas of the retina away from the macula are treated with scattered laser burns,” explains Dr Badawy. “The burns cause the abnormal new blood vessels to shrink and scar. Some loss of peripheral vision or night vision after the procedure is possible.”

Lastly, there is vitrectomy, a procedure that uses a tiny incision in the eye to remove blood from the middle of the eye as well as any scar tissue attached to the retina. “Treatments can slow or stop the progression of diabetic retinopathy but it’s not a cure,” says Dr Badawy. “Diabetes is a lifelong chronic disease, future retinal damage and vision loss are still possible. That’s why regular follow-up and treatment are needed.”

How to meet your ocular needs

Neeraj Dabral, Assistant General Manager, Aster Opticals, talks about what’s better - eyeglasses or contact lenses

Are glasses better for the eyes or contact lenses ?

Glasses and contact lenses go hand in hand when it comes to correcting vision. They complement each other and differ only by their usage. Contact lenses are ideal while playing sports, leading an active lifestyle, imitating natural vision, changing eye colour and cosmetic reasons. Eyeglasses are the go-to vision correction eyewear. They

are easier to maintain, and frames come in a variety of shapes, colours and sizes. They serve a dual purpose of being a fashion accessory and vision correction method. It’s recommended to use both eyeglasses and contact lenses based on usage for a more fulfilling experience aligned to your lifestyle needs.

Neeraj Dabral

Neeraj Dabral, Assistant General Manager, Aster Opticals

How often should people get an eye exam done?

As recommended by the American Optometric Association, eye checkups should be done annually as emphasised by their Check Yearly See Clearly campaign. While annual checkups might serve well for most people, those with chronic conditions like diabetes, heart problems, hypertension, etc. might need to get their eye checkups done at a more frequent interval. These are just guidelines. Your eye care practitioner might suggest a different exam schedule to meet your ocular needs.