About diabetic retinopathy
What are the symptoms of diabetic retinopathy?
Symptoms become noticeable a while after medical signs have been present. If diseased blood vessels have become leaky they will cause macula oedema and you will have the symptom of blurry vision.
If some of the new blood vessels are starting to bleed, you may notice spots in your field of vision. They are flecks of blood and may disappear, but the cause is still present. At some point, spots will reappear, and more of them.
Diagnosing Diabetic Retinopathy
If you have diabetes and you notice spots floating in your vision, please call us immediately.
Dr. Thomas Eshun-Wilson will give you a thorough eye exam including a vision test, a dilated eye exam (to look closely at the retina and optic nerve), and a test of your eye pressure (intraocular pressure, IOP for short). He will look for leaking blood, changes in the capillaries, damaged nerves, retinal swelling, and fatty deposits on the retina that are signs of leaking blood.
If necessary, he will order a fluorescein angiogram. This is a procedure to get clear images of any new blood vessels behind the retina. It involves injection of a fluorescent dye to the hand or arm. The dye travels in the bloodstream, entering the retinal capillaries after a few seconds. Over about one minute, a series of photos is taken and you will have a bright light flash into your eye each time. It will not harm your eyes. Afterwards, you may notice a yellow tint in your skin, as the dye is yellow, but it will disappear in a day.
There are Four Stages of Diabetic Retinopathy
- Mild Non-Proliferative Retinopathy – Small areas of swelling develop in the retinal capillaries, called microaneurysms. You would probably not notice any change in your vision at this stage.
- Moderate Non-Proliferative Retinopathy – Some of the capillaries become blocked and bleed into the retina.
- Severe Non-Proliferative Retinopathy – Many more capillaries become blocked. Now the retina has insufficient blood supply and the body will respond by starting to grow new blood vessels behind the retina in the next stage.
- Proliferative Retinopathy – new capillaries grow on the retina and also on the surface of the fluid that fills most of the eyeball and bathes the retina (called vitreous gel). These capillaries are fragile and they leak. Leaked blood and fluid interferes with vision – you would see dark patches in your field of vision as if someone had spilled black ink on the picture. If nothing is done, there will be blindness at this stage.
As this disease progresses through the four stages, blood and fluid may leak into the retina’s central area, the macula. It causes the macula to swell (macular oedema). This blurs your central, direct vision, the vision you need for reading and other detailed activity. It happens in about 50% of cases.