When you have diabetes, it’s important to watch out for other serious health problems that can come along with it. Eye disease is a common condition that happens with diabetes. Blood sugar spikes can damage blood vessels throughout the body, including those in your eyes.
Diabetic retinopathy is one type of eye disease caused by diabetes. It happens when your blood sugar is too high and damages your retina, the tissue that lines the inside of the eye. The retina’s job is to take in light and transfer signals to your brain via a nerve at the rear of your eye called the optic nerve. Small blood vessels connected to your retina leak fluid or bleed when sugar damages them. Your eyes do grow new blood vessels, but they’re weaker and have trouble keeping in blood and fluids.
What Is Diabetic Macular Edema?
Diabetic retinopathy may lead to another eye condition: diabetic macular edema or DME. It’s the most common cause of vision loss in people with diabetic retinopathy.
DME happens when fluid, blood, or cholesterol leaks from blood vessels in your retina. The fluid then causes the central part of the retina (called the macula) to swell.
Progression of Diabetic Macular Edema
DME can happen at any stage of diabetic retinopathy. It’s possible to have mild diabetic retinopathy and severe DME. There’s no timeframe for how long it might take for DME to become serious or a scale to measure its progression. In general, your doctor will watch out for two things during eye exams: the level of swelling and where it’s located.
With DME, your vision becomes blurred or wavy near the center of your field of vision. Colors could look dull or washed out. Some people with the condition don’t have symptoms, but most will have symptoms that span from mild blurriness to distinct vision loss. It’s also possible to only have vision problems in one eye.
Doctors usually link more serious symptoms of DME with swelling of the retina. The more swelling you have from leaking fluid and the closer it is to the center of the eye, the more likely you are to have vision problems.
Since you may not have any symptoms of DME, it’s critical to get a diabetic eye exam at least once a year. To check for the condition, your eye doctor will dilate your pupils to widen them and take images of the retina. The imaging test, called optical coherence tomography or OCT, will show your doctor if the retina is thickened with fluid and where in the eye it’s happening.
Your doctor may also use another imaging test called fluorescein angiography (FA). They’ll put dye in an arm vein, which travels in your blood to your eye. A special camera then captures enhanced images and shows doctors if fluid is leaking into your retina. The test also helps your doctor to track any eye changes over time.
Your doctor will talk about treatment options if DME is close to the central part of your eye and affects your vision. The first thing they’ll suggest is to control your blood sugar. They may also recommend these treatments to repair damage to the retina:
- Anti-VEGF injections. Your doctor will first apply special drops to your eye to numb it, then use a needle to inject medicine. The medicine blocks a protein called VEGF that encourages the growth of new blood vessels that are more fragile than those found in healthy eyes.
- Anti-inflammatory treatments. Steroid injections ease inflammation in the eye.
- Laser. Doctors use laser-guided heat to repair leaking blood vessels in your retina.
- Surgery. You may need surgery to correct your vision or remove blood or gel (called vitreous) that builds up in the eye.
Anti-VEGF injections are the main treatment for severe swelling of the retina. Doctors will use laser therapy for DME that doesn’t affect the center part of your eye.
Purnima Patel, MD, clinical spokesperson, American Academy of Ophthalmology.
AJMC: “Overview of Diabetic Macular Edema.”
National Eye Institute: “Macular Edema,” “Diabetic Retinopathy.”