What are the symptoms of diabetic macular edema?

Diabetic macular edema (DME) is a complication of diabetes—and more specifically, a complication of diabetic retinopathy.

Diabetic retinopathy is damage to the small blood vessels that supply a part of the eye called the retina. The retina is a layer of light-sensitive cells in the back of the eye. Diabetic retinopathy occurs as a result of uncontrolled blood glucose levels, which causes damage to blood vessels.

Diabetic retinopathy progresses through multiple stages, with symptoms appearing in the middle and later stages. In the early stages, symptoms may be fleeting, nonexistent, or otherwise unnoticeable, and someone can have diabetic retinopathy without knowing it.

With DME, damaged blood vessels in the eye leak fluid into the macula, the central part of the retina. This causes the macula to fill with fluid and swell. DME can develop at any stage of diabetic retinopathy, even the early stages, though it is more common in the advanced stages.

What are the symptoms of DME?

The main function of the macula is central vision. Central vision refers to the eye’s ability to see details, enabling a person to read, recognize faces, operate a vehicle, and distinguish objects and colors. For these reasons, central vision is considered the most important part of a person’s vision.

DME impairs and reduces central vision. Symptoms can include:

• Blurred vision
• Double vision
• An increase in floaters
• Straight lines that appear bent or wavy
• Difficulty seeing in low light, bright light, or when exposed to glare
• Changes in the ability to see colors, such as colors appearing dulled or washed out
• The same object appearing to be different sizes when looking at it with one eye compared to looking at it with the other

The severity of DME can vary from person to person. Some people may only experience slightly blurry vision. For others, DME causes significant vision loss that limits the ability to perform everyday tasks like driving, reading, or recognizing faces.

Vision problems like these can make it difficult to perform many of the tasks required to manage diabetes, such as preparing meals, reading instructions for medications, and exercising. This can potentially lead to worsening diabetes control—and more severe diabetes complications, including more severe eye and vision problems.

How is DME treated?

Vision problems like diabetic retinopathy and DME often become more severe with time, especially when left untreated. Diabetes complications are a leading cause of vision impairment and blindness. Seeking treatment is the best thing a person can do to prevent further vision loss and should not be delayed—early diagnosis and treatment are associated with better treatment outcomes.

There is no cure for DME, but there are treatments that can help slow progression, and in many cases, improve vision. Diabetes control is an essential part of treating DME.