Diabetic Retinopathy

​

Diabetic retinopathy is a complication of diabetes, caused by high blood sugar levels damaging the back of the eye (retina). It can cause blindness if left undiagnosed and untreated. However, it usually takes several years for diabetic retinopathy to reach a stage where it could threaten your sight.

 

Understanding how the eye works

​

​

Our eyes are like a camera.  The iris and the pupil control how much light come into the eye, the lens helps focus the light to create a clear picture on the retina.  The retina is a light-sensitive layer at the back of the eye that acts like the film in a camera.  It captures the images focused by the lens and sends the images as signals to the brain.  The macula is the center of the retina and is responsible for detailed central vision.  The optic nerve sends signals from the retina to the brain to interpret the image.

​

What is Diabetic Macular Edema (DME)

​

In patients with diabetes elevated blood sugar levels can result in damage to the blood vessels of the body, including the retina.  These retinal blood vessels become weak and can begin to leak fluid into the back of the eye (macula), causing it to swell and thicken. The swelling of the macula, also known as macular edema, can affect the way images are seen on the macula, making them appear blurred.  DME can occur in patients with type 1 and type 2 diabetes.  

​

In people with diabetes, the high blood glucose levels in the blood vessels of the retina can lead to damage of the surrounding tissue and a reduction in the oxygen and nutrient supply to the retina.  The high blood glucose level results in the weakening of the blood vessels, making the walls of the vessels more permeable or leaky.  This leakiness is what causes the edema in your macula.  The macula is responsible for your central vision and when DME develops it can make reading and drive difficult.  As your disease progresses blood vessels may bleed into the eye causing you to see floaters/spots in your vision.  The spots may clear temporarily, but the bleeding may continue and damage your vision if left untreated.  Some symptoms of DME are blurry central vision, straight lines appearing wavy, colors looking washed out / faded, you may see blotches or spots in your central vision, and in some cases sudden loss of vision.  Symptoms vary from person to person.

​

DME can be treated with a series of intravitreal anti-VEGF injections. The most commonly used anti-VEGF drugs are Eylea, Avastin, and Lucentis.  The drug you receive will depend on the severity of your disease, age, and financial coverage options.

​

What is Proliferative Diabetic Retinopathy (PDR)

​

PDR is the more advanced form of the disease. At this stage, circulation problems deprive the retina of oxygen. As a result, new, fragile abnormal blood vessels can begin to grow in the retina and into the vitreous.  These abnormal blood vessels can occasionally leak and cause a vitreous hemorrhage (bleed in at the back of the eye).  A small vitreous hemorrhage will cause dark floaters while a large hemorrhage may block all your vision.  The new blood vessels can also cause scar tissue to grow.  The scar tissues shrink, wrinkling and pulling on the retina, which can cause distortion in your vision.  If the pulling is severe it can cause retinal detachment which requires surgical intervention.  

​

PDR can be treated with a series of intravitreal anti-VEGF injections as well as a series of lasers called panretinal photocoagulation (PRP). If you develop a vitreous hemorrhage that does not respond to treatment you may require surgery called a vitrectomy to remove the blood from the eye.

 

Living with Diabetic Retinopathy

​

Anti-VEGF therapy has been shown to help slow the vision loss from DME, however, there are some simple lifestyle changes you can make to slow the progression of the disease.  They are as follows:

​

• Keep your blood glucose (blood sugars) in check. Maintaining appropriate blood sugar levels has been shown to result in fewer eye problems

• Watch your blood pressure and cholesterol level.

• Make sure to keep your regularly scheduled appointments with Dr. Varma to ensure close monitoring of your disease.

• Monitor and report any vision changes to the office as soon as possible. You will be given an Amsler grid and instructed on its proper use. This is a grid or series of horizontal and vertical lines with a black dot in the center.  When you look at the grid you will focus on the black dot and check to see how the lines appear to you.  When you first start using the grid you may already have some areas of distortion and it is helpful to mark these areas. You should check your Amsler grid daily with each eye separately and report any new areas of distortion.

• Do not smoke, if you do smoke you should consider stopping even if it means speaking to your family physician to get help.

• Eat a healthy well-balanced diet with fresh fruit, dark green leafy vegetables, foods high in Omega 3s (ie: fish and nuts).

• Exercise regularly to maintain a healthy weight.

• Wear sunglasses to protect your eyes from UV rays.

​

Coping with vision loss​

​

Vision loss can be challenging and life-changing.  It can impact your everyday life and make you less independent.  It will take time to adjust to living with vision loss whether it be minimal or extensive.  The CNIB (Canadian National Institute for the Blind) has many resources for coping with vision loss.  If this is something you are interested in Dr. Varma can refer you to them.