What is macular edema?

03 November 2022

Macular edema is swelling of part of the retina, the light-sensitive layer of tissue at the back of the eye. People with macular edema may have blurred vision, but treatment can help reduce swelling and prevent vision loss.

The main symptoms of macular edema are blurred vision and worsening vision over time.

You may also notice that:

• Objects appear wavy, especially when you look straight ahead.
• Objects appear to be different sizes if you look out of one eye and then the other.
• Colors appear dull or faded.

If you only have macular edema in one eye, it may take longer to notice changes in your vision.

For some people, macular edema causes only mild blurred vision. For others, it causes more severe central vision loss, which can make it difficult to perform everyday activities, such as reading or driving.

There are many different conditions that can cause macular edema, the most common being diabetic retinopathy, an eye disease that causes vision loss in people with diabetes. When diabetic retinopathy causes macular edema, it is called diabetic macular edema (DME).

If you have diabetic retinopathy, controlling your diabetes can help prevent or delay vision loss. Ophthalmologists can check for macular edema through a dilated eye exam, which involves applying eye drops to widen the pupil and look at the retina. The test is simple and painless, and it is important to perform it at least once a year.

If your doctor suspects you have macular edema, he or she may order other tests to confirm it, such as:

• Fluorescein angiography. This test allows the ophthalmologist to see images of the blood vessels in your retina. Your doctor will inject a special dye into your arm, which travels through your bloodstream to your eye. The doctor will then use a camera to take pictures of the back of your eye as the dye flows through the blood vessels of the retina.

• Optical Coherence Tomography (OCT). This test allows the doctor to see the back of your eye by capturing images of the retina and other parts of the eye with a special machine. In this way, the doctor can see the degree of inflammation.