What is Macular Edema?

Macular edema happens when fluid builds up in the macula (usually due to a leak from blood vessels damaged by diabetic retinopathy), causing swelling. This can distort vision, making things look blurry and colors look washed out.

What causes Macular Edema?

There are many conditions that can leak fluid into the retina and cause macular edema, including:

• Diabetes. With diabetes, high blood sugar levels damage blood vessels, which leak into the macula.
• Age-related macular degeneration (AMD). With AMD, abnormal blood vessels leak fluid and cause macular swelling.
• Macular pucker/vitreomacular traction. When vitreous in the aging eye doesn’t detach completely from the macula, the vitreous tugs on the macula or forms scar tissue, and pockets of fluid collect underneath it.
• Retinal vein occlusion (RVO). With blood vessel diseases like RVO, veins in the retina become blocked. Blood and fluid then leak out into the macula.
• Hereditary/genetic disorders (passed from parent to child), such as retinoschisis or retinitis pigmentosa.
• Inflammatory eye diseases. Conditions like uveitis, where the body attacks its own tissues, can damage retinal blood vessels and cause swelling of the macula.
• Medication. Certain drugs have side effects that can lead to macular edema.
• Eye tumors. Both benign and malignant tumors can lead to macular edema.
• Eye surgery. It’s not common, but sometimes after glaucoma, retinal, or cataract surgery, you can get macular edema.
• Injuries. Trauma to the eye.

Symptoms

Macular edema is painless and usually doesn’t have symptoms when you first get it. When you have symptoms, they are a sign that the blood vessels in your eye may be leaking.

Common symptoms of macular edema include:

• Blurred or wavy central vision.
• Colors appear washed out or different.
• Having difficulty reading.

Diagnosis

In addition to a routine ophthalmic examination, which includes examination of visual acuity (far and near), measurement of intraocular pressure, examination of the anterior segment of the eye and study of the fundus, patients with macular edema may require complementary examinations, among which fluorescein angiography and optical coherence tomography stand out.

Treatment

The best approach to treatment requires addressing the underlying cause of the macular edema, and the related leakage and retinal swelling.

Treatment for macular edema depends on what’s causing it, and can include:

Laser treatment. With this surgery, the ophthalmologist applies many tiny laser pulses to areas of fluid leakage around the macula. The goal is to stabilize vision by sealing off leaking blood vessels.

Intravitreal injections. There are medications called anti-VEGF drugs. Anti-VEGF treatment helps reduce abnormal blood vessels in your retina, and also decreases leaking from blood vessels. This medicine is delivered to your eye through a very slender needle.

Steroid treatment. When macular edema is caused by inflammation, steroid medication may be used. These drugs can be given by eye drops, pills, or injections.

In those cases of macular edema that appears after cataract surgery, topical medical treatment with non-steroidal anti-inflammatory drugs is indicated.
When macular edema is caused by the traction of the vitreous humor on the macula, a surgical procedure, called a vitrectomy, may be necessary to restore normality to the macula.
Depending on the cause of the macular edema and the recommended treatment plan, it can take several months for macular edema to resolve.