Diabetic retinopathy is an eye disease caused by diabetes. Elevated blood glucose levels result in a) damaged blood vessels and b) growth of abnormal new blood vessels in the retina. Damaged and abnormal blood vessels can swell and leak. Or they can close, stopping blood from passing through. All of these changes can result in permanent loss of vision.
The Two Stages of Diabetic Retinopathy:
1) NPDR (Non-Proliferative Diabetic Retinopathy)
This is the earlier stage of diabetic eye disease. Many people with diabetes have it.
With NPDR, tiny blood vessels leak, making the retina swell. When the macula swells, it is called diabetic macular edema (DME). This is the most common reason why people with diabetes are blurry and complain of vision loss.
Also with NPDR, blood vessels in the retina can close off. This is called ischemia. It is referred to as macular ischemia when this occurs in the macula. With ischemia, blood cannot reach that portion of the retina. Sometimes tiny particles called exudates can accumulate which also affect vision. Widespread ischemia often leads to PDR.
Color fundus photo (A) of a patient with NPDR and DME showing microaneurysms, retinal hemorrhages, and hard exudates. Fluorescein angiogram (B) of the same patient showing extensive leakage, microaneurysms, and capillary nonperfusion (ischemia).
PDR is the more advanced stage of diabetic eye disease. It happens when the retina starts growing new blood vessels, a process called retinal neovascularization. These fragile new vessels often bleed into the vitreous. If they only bleed a little, you might see a few dark floaters. If they bleed a lot, it might block all vision.
These new blood vessels can lead to formation of scar tissue. Scar tissue can be devastating by causing problems with the macula and/or leading to tractional retinal detachment.
PDR is very serious and unless addressed and treated properly it results in permanent central and peripheral (side) vision loss.
Patient with PDR showing extensive retinal neovascularization, less evident on fundus photography (A) than on retinal fluorescein angiography (B).
What Are Symptoms of Diabetic Retinopathy?
You can have diabetic retinopathy and not know it. This is because it can have no symptoms in its early stages. As diabetic retinopathy gets worse, you often notice symptoms such as:
- seeing an increasing number of floaters,
- having blurry vision,
- having vision that changes sometimes from blurry to clear,
- seeing blank or dark areas in your field of vision,
- having poor night vision, and
- noticing colors appear faded or washed out
- losing vision.
Diabetic retinopathy symptoms usually affect both eyes.
How Is Diabetic Retinopathy Diagnosed?
Ancillary testing including a scan of the retina using a machine called optical coherence tomography (OCT) is done which provides detailed images to evaluate your macula. Fluorescein angiography (FA) helps your retina specialist evaluate the blood vessels in your retina. It uses a yellow dye called fluorescein, which is injected into a vein (usually in your arm). As the dye travels through your blood vessels, a special camera takes photos of the retina and demonstrates areas of ischemia, leakage, and neovascularization. FA is used to determine the degree of nonperfusion and the presence of retinal vascular abnormalities to differentiate between the stages of diabetic retinopathy and plan appropriate treatment.
How is Diabetic Retinopathy Treated?
Your treatment is based on what your retina specialist finds during your evaluation. As such, a thorough retinal exam and review of the necessary ancillary diagnostic tests are imperative. Treatment options may include:
Systemic control
Medications
One type of medication used to treat diabetic retinopathy is called anti-VEGF medication. These include Avastin, Eylea, Lucentis, Cimerli, Vabysmo, among others. Anti-VEGF medication help in several ways, including by reducing swelling of the macula, slowing vision loss, and perhaps improving vision. This drug is given by the form of injections in the eye. Steroid medicine is another option to reduce macular swelling. This is also given as injections in the eye. Your retina specialist will recommend the best way to proceed to treat your diabetic retinopathy over time based on your findings.
Laser Surgery
When it comes to treating diabetic retinopathy, there are different types of laser surgeries that can be utilized to achieve various goals. One particular laser procedure might be used to reduce swelling. Another laser treatment is used to shrink abnormal blood vessels and prevent them from growing again and leading to vitreous hemorrhage or tractional retinal detachment. More often than not repeated laser treatments will be required.
Vitrectomy
If you have advanced PDR you may require a surgery called vitrectomy. This is when the vitreous gel and any blood from leaking vessels are removed from the back of your eye. This allows light rays to focus properly on the retina again. Scar tissue might also be removed from the retina.
5 Ways to Prevent Vision Loss from Diabetic Retinopathy
- If you have diabetes, talk with your primary care doctor about controlling your blood sugar. You may benefit from seeing a nutritionist to help modify your diet to reach your goals. High blood sugar damages retinal blood vessels. That causes vision loss.
- Do you have high blood pressure or kidney problems? Ask your doctor about ways to manage and treat these problems.
- See your ophthalmologist regularly for dilated eye exams. Diabetic retinopathy may be found before you even notice any vision problems.
- If you notice vision changes in one or both eyes, call for an evaluation right away.
- Get treatment for diabetic retinopathy as soon as possible. This is the best way to prevent vision loss.
Source: American Academy of Ophthalmology