DIABETES AND VISION
WHAT IS DIABETES?
AND HOW DOES IT AFFECT VISION?
Diabetes is a serious chronic illness that affects 537 million people globally and continuous to affect more and more people every year. In diabetes, the pancreas is either unable to produce enough insulin to regulate blood sugar or the body cannot effectively use the insulin it produces.
In cases of unregulated diabetes, raised blood sugar (hyperglycaemia) over time leads to serious damage to many organs.
Not only are diabetics two to three times more likely to suffer from heart attack or stroke, but are more likely to experience reduced vision or blindness as a result of damage to the blood vessels of the retina (the posterior part of the eyes). It is estimated that close to 1 million people worldwide are blind due to diabetes.*
Diabetes can lead to vision loss in different ways. Two of the most common problems are macular edema and retinopathy. Furthermore, diabetes can also make you more likely to have other eye problems, such as cataract and glaucoma.
To understand exactly how diabetes affects the eyes, think of the eye as a camera where the light passes through the transparent lens to display an image in back wall of the eye. This wall, called the retina, is filled with light-sensitive cells that are dependent on tiny blood vessels for nourishment. When one has diabetes, these tiny blood vessels can become damaged, resulting in damage to the retinal tissue as well.
This damage can make the blood vessels “leaky” and fluid will accumulate into the retina. This will in turn cause the retina to thicken and swell, which can lead to blurry vision, a condition called macular edema.
In retinopathy, small blood vessels are so severely damaged from hyperglycemia over time, that the starving retina creates new blood vessels on its surface, a process called proliferative retinopathy. These new blood vessels unfortunately break and bleed easily, causing scar tissue to form. Over time this scar tissue will build up and stretch the retina, eventually separating it from the wall of the eye. When the retinal tissue is separated from its blood supply it will die, causing loss of vision in the affected areas. This can process can happen suddenly or slowly over time.
When you are diabetic it is important to schedule an annual dilated eye exam as you might not necessarily have any notable symptoms and even perfect vision until serious damage has already occurred. However, some of the early signs may include:
Trouble seeing at night
Blurry vision in only one eye
Redness or pain in your eye
Seeing floaters, spots or “flies”
Loss of peripheral vision
Please note that if you suddenly start seeing floaters, spots/”flies” or experience sudden loss of middle or peripheral vision (patients often describe it as a dark curtain in the middle or on the side of their visual field), this can indicate a retinal break and a detached retina. Retinal detachment must be treated as soon as possible to avoid blindness.
ANNUAL EYE CHECK-UPS ARE A MUST!
In addition to managing and controlling your diabetes through a healthy diet, medication and exercise, you should schedule a dilated eye exam once a year, or even more often if you have a known eye problem.
At our clinic we offer all patients a comprehensive eye exam, in order to exclude both common as well as rare diseases and conditions. Most exams take approximately 45-60 minutes.
We will check for changes to your glasses or contact lens prescription, eye pressure, clouding of the lens, and if you suffer from dry eyes, we can test your tear production. To properly examine the retina, the doctor will give you eyedrops that dilate your pupils and take about 20-30 min to work.
WHAT TREATMENT OPTIONS ARE THERE?
There are several treatments that can help manage and restore vision caused by diabetes.
Anti-VEGF (anti-vascular endothelial growth factor) therapy, which involves injecting drugs into the eye to stop the leaking blood vessels
Steroids to reduce inflammation and retinal swelling
Photocoagulation (laser therapy) to seal the blood vessels and treat the dead retinal tissue
Vitrectomy, a surgery that can remove blood from inside the eye, scar tissue and fix the retinal detachment, saving the vision
(*) Causes of blindness and vision impairment in 2020 and trends over 30 years, and prevalence of avoidable blindness in relation to VISION 2020: the Right to Sight: an analysis for the Global Burden of Disease Study GBD 2019 Blindness and Vision Impairment Collaborators* on behalf of the Vision Loss Expert Group of the Global Burden of Disease Study† Lancet Global Health 2021;9:e141-e160.