Macular edema refers to swelling at the center of the retina, which is the layer at the back of the eyeball. It occurs when blood or fluid leaks into the retina and builds up, which can result from many conditions, including diabetes. Treatments may help prevent vision loss.

Without treatment, macular edema might lead to severe vision problems. However, treatments can help address the underlying causes and reduce swelling.

Read on to learn more about macular edema. This article examines symptoms and causes, how doctors diagnose macular edema, treatment options, and more.

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Macular edema does not cause pain, and symptoms often do not develop until blood vessels start to leak.

When symptoms occur, macular edema mainly causes blurred vision. Vision will also gradually worsen over time.

People with macular edema might find that they notice the following changes in their vision:

  • Straight lines may become wavy, particularly if a person looks straight ahead.
  • An object might appear to be a different size depending on the eye a person uses to look at it.
  • Colors may appear duller or more faded than before.
  • Reading may become difficult.

Without treatment, macular edema can lead to irreversible eye damage and permanent vision loss.

Learn about other causes of blurry vision.

Macular edema occurs when fluid or blood leaks into the retina. This builds up and causes swelling, resulting in changes in a person’s vision.

The cells of the retina line the back of the eye, sensing light and sending signals to the brain. This is how the eye creates images. The macula sits at the center of the retina, allowing the eye to see color, distant objects, and small details in the visual field.

Macular edema occurs when this area of the retina swells. However, macular edema is not an eye condition on its own. Instead, it usually develops due to conditions that cause fluid to leak into the back of the eye.

Learn more about retinal conditions.

Several underlying conditions can increase a person’s risk of macular edema.

Diabetic retinopathy is the most common cause of macular edema. High blood sugar levels damage the blood vessels in the retina, which can cause blood to leak and contribute to macular edema. Doctors refer to macular edema resulting from diabetes as diabetic macular edema (DME).

A 2022 review of seven studies suggested that around 5.14% to 5.47% of people with diabetes have DME.

Other causes of macular edema include:

If a person has any concerns about the risk factors for macular edema, they can contact their eye doctor. Attending regular eye tests can also help eye doctors detect signs of macular edema as early as possible.

If an ophthalmologist, a type of eye doctor, suspects macular edema, they may use eye drops to expand the pupils and examine the eye.

The doctor may then perform various tests to help confirm the diagnosis.

Fluorescein angiography

Fluorescein angiography involves injecting a yellow dye into a vein in the arm. This then travels through the blood vessels, including those at the back of the eye.

The ophthalmologist can use a specialized camera to create images of the retina as the dye travels through it, showing the location and extent of any blood vessel leakage.

Optical coherence tomography (OCT)

OCT uses highly detailed cameras. The resulting images show the thickness of the macula, allowing an ophthalmologist to see how swollen it is and where leakage may be occurring.

Amsler grid

The ophthalmologist may also use an Amsler grid to identify problems with the center of a person’s visual field.

An ophthalmologist shows the individual a grid of lines. If part of it looks wavy, they may investigate central vision loss, which is a symptom of macular edema.

Macular edema treatment aims to prevent vision loss. The main treatment involves addressing the underlying condition. For example, if it develops due to diabetes, taking steps to control blood sugar will be key to reducing the effects of DME.

People can also take steps to manage macular edema directly. Possible treatments include:

  • Injections: Doctors may inject antivascular endothelial growth factor (anti-VEGF) medications to slow or reverse macular edema. Injectable steroids can also help reduce swelling in the macula.
  • Eye drops: Nonsteroidal anti-inflammatory drugs (NSAIDs) are available in eye drop form. These are helpful for macular edema that develops as a side effect of eye surgery.
  • Laser treatment: If injections do not successfully reverse macular edema, a doctor may recommend laser surgery. This can help treat macular edema resulting from other health problems, including diabetes or retinal vein occlusion.
  • Vitrectomy: If other treatments do not help, vitrectomy surgery may be beneficial. A surgeon removes the gel that fills the eye through small openings in the eye wall using a suction device. They may also implant an opening that makes future injections easier.

Below are answers to common questions about macular edema.

How serious is macular edema?

Not all types of macular edema are serious. For example, it may be possible to reverse macular edema due to the side effects of medication.

However, without treatment, macular edema can lead to vision loss and blindness. According to a 2023 review, it is the most common cause of vision loss in people with diabetes. It can also lead to glaucoma, which is increased pressure within the eye.

What is the best treatment for macular edema?

The best treatment for macular edema depends on the cause. Possible treatments include addressing the underlying cause, anti-VEGF injections, steroids, NSAID eye drops, laser treatment, and vitrectomy surgery.

What are the best eye drops for macular edema?

The best eye drops for macular edema depend on which type of macular edema a person has. Doctors may recommend steroids, NSAIDs, or dorzolamide eye drops. People may need to take these for a few months before symptoms start to improve.

Can macular edema resolve itself?

Some cases of macular edema have resolved without treatment. However, if symptoms develop, it is important to consult an eye specialist as soon as possible. Treatment is often necessary to prevent irreversible damage to vision.

What should you avoid if you have macular edema?

No specific guidance is available on lifestyle changes with macular edema. If symptoms develop, a person needs to contact an eye doctor. It is also important to regularly attend eye appointments.

Can you have macular edema without diabetes?

A person can have macular edema without diabetes, as there are many other possible causes, including AMD, vitreous pulling on the macula, retinal vein occlusion, uveitis, and tumors. Eye surgery, injury to the eye, and certain medications can also cause macular edema.

Macular edema is swelling of the macula due to leaking fluid from blood vessels. It does not cause severe symptoms at first but can eventually lead to blurry and worsening vision, especially at the center of the visual field.

The most common cause is diabetes, but age-related macular degeneration, retinal vein occlusion, tumors, and other conditions can lead to macular edema.

Without treatment, vision loss and blindness may develop. The best treatment depends on the underlying cause and might include eye drops, injected medications, or laser surgery. Vitrectomy surgery may be suitable if other options do not resolve symptoms.