By Sunir Garg, MD, as told to Hallie Levine
Diabetic retinopathy, a type of diabetic eye disease, is one of the leading causes of blindness in the United States. Despite this, almost 40% of people with diabetes don’t get an annual eye exam. But these screening tests are key, since they can prevent vision loss by catching diabetic retinopathy in the early, more treatable stages of disease.
Diabetic retinopathy can cause permanent vision loss.
Many people are surprised to learn that diabetic retinopathy is the most common cause of vision loss for people with diabetes. Here’s a quick primer.
Diabetes is a disease that affects the small blood vessels throughout the body, including the delicate blood vessels in the back of your eye. These blood vessels are just like pipes: When they become damaged, they weaken and start to leak. Over time, these tiny blood vessels drip blood and plasma onto your retina. This causes retinal tissue to swell, which leads to cloudy or blurred vision. This also causes damage that results in less oxygen and other nutrients getting to your retina.
Sometimes, your body tries to correct the problem by making new blood vessels. But these blood vessels are fragile and can burst and bleed, or form scar tissue that pulls your retina off of your eye wall. All of these scenarios may ultimately lead to blindness.
You can have diabetic retinopathy and not know it.
The condition often has no symptoms in its early stages, which is why an annual eye exam is so important. As it worsens, you may notice symptoms like:
- Blurry vision
- Vision that changes from blurry to clear
- Blank or dark areas in your field of vision
- Floaters, or dark spots in your vision
- Poor night vision
- Colors appear faded
Unfortunately, patients often don’t see an eye specialist until they experience symptoms such as floaters or blurry vision, and by then damage has been done.
There’s a lot you can do to treat diabetic retinopathy.
When we notice signs of diabetic retinopathy during a patient’s routine eye exam, they’re often very frightened. They worry that they will lose their vision. But most of the time, their disease is mild. We explain that the best way to stop vision loss is to make sure their blood sugar and blood pressure are both under good control. They need to watch their diet carefully and take all their medications as prescribed. Oftentimes, we show patients a picture of their eyeball so they can see the damage their diabetes has done. That’s usually enough to help them understand why blood sugar and blood pressure control are so critical to help their overall well-being.
But if your disease is more advanced, don’t panic. The first step is a class of drugs known as anti-VEGFs. These medications help reduce eye swelling, which can slow down vision loss and even improve vision. It’s given as a shot, injected into your eye at your eye specialist’s office. Laser surgery can also help seal off leaking blood vessels, shrink abnormal blood vessels, and reduce retinal swelling. If you have a very advanced case, you may need a type of eye surgery known as a vitrectomy. An eye surgeon will remove blood and plasma from your eye and remove scar tissue from your retina. This will also help you to see more clearly again.
Regular eye exams are key.
People with diabetes need to have a routine eye exam every year by an eye doctor (either an ophthalmologist or an optometrist). This is true even if you otherwise have 20/20 vision. Your doctor will give you some eye drops to dilate, or widen, your pupils so that they can look inside your eyes to check them for diabetic retinopathy and other eye problems.
If you’ve just been diagnosed with diabetes, you need an eye exam right away to make sure your eyes are OK. After that, you should have an eye exam every year -- more frequently if you have diabetes-related eye problems such as diabetic retinopathy.
There are also other times in your life when you may need a full eye exam. Women with diabetes who are pregnant, for example, need an eye exam during every trimester, since changes in blood pressure and fluid retention may cause their diabetes to worsen.
Interestingly enough, you also need to get your eyes checked once you get your diabetes under good control. For some reason, that shift can cause some worsening of diabetic eye disease in certain patients. We don’t know why, other than your body has gotten used to things being a hot mess and your eyes don’t know how to cope with this sudden change.
The good news is that most patients with diabetes who get regular eye exams who do go on to develop diabetic retinopathy end up doing very well. When we monitor them appropriately and treat problems when they creep up, we can keep the vast majority of patients seeing quite well for years, sometimes even an entire lifetime. But both the doctor and the patient must work together to make that happen.