Macular oedema

Macular oedema

Macular oedema is an effect of the accumulation of fluid in the macula. As a result, objects are distorted, with blurry vision and faded colours. Left untreated, macular oedema can lead to permanent loss of central vision.

What causes macular oedema?

Macular oedema is caused by accumulation of fluid in the macula (usually leaking out of the blood vessels). The reasons for the leakage of fluid into the retina can be different:

• Diabetes. High blood sugar level may damage the blood vessels and cause leakage of fluid into the macula.
• Age-related macular degeneration (AMD). Leakage of fluid from abnormal blood vessels leads to macular oedema.
• Epiretinal membrane or vitreomacular traction. With age, the vitreous may not completely separate from the macula. In this case, it tightens the macula, or connective tissue (scar) forms on the macula with accumulation of fluid.
• Retinal vein occlusion and other blood vessel diseases can lead to clogged retinal veins. As a result, blood and fluid may flow into the retina.
• Hereditary and genetic disorders (inherited by children from parents). Uveitis and other diseases, when your body attacks its own tissues, can damage retinal blood vessels and swelling of the macula.
• Medications. Side effects of some medications lead to macular oedema.
• Tumours of the eye. Benign and malignant tumours of the eye can lead to macular oedema.
• Eye surgery. Macular oedema rarely occurs after surgery for glaucoma, cataracts, or after surgery on the retina.
• Eye injuries.

Terms

Vitreous is a transparent gel which fills the eye cavity from the inside, maintains the rounded shape of the eye and transmits light rays to the retina.

Retina is a layer of nerve cells, located on the inner surface of the eye. The retina senses light and sends signals to the brain, with images formed out of these signals in the brain.

Macula is a small but very important area in the centre of the retina. Macula is needed to clearly see the small details of objects.

What are the symptoms of macular oedema?

Macular oedema is not painful and usually does not have any symptoms at the initial stage.

Any of the following symptoms usually indicates fluid leaking from the blood vessels in the eye.

The symptoms of macular oedema are:

• blurring or deformation of objects in the centre of the field of vision;
• colours are perceived as faded or not the same as they are;
• reading difficulties.

If you notice any symptoms of macular oedema, see your ophthalmologist immediately. Left untreated, macular oedema can lead to significant vision loss.

How is macular oedema diagnosed?

To diagnose macular oedema, an ophthalmologist needs to examine the retina with a special lens, after dilating the pupil with eye drops.

Perhaps the ophthalmologist will conduct additional examinations:

Fluorescence angiography. A yellow dye (fluorescein) is injected into a vein of your arm. Through the blood vessels, the dye enters the retina, and at this time it is photographed with a special camera. This method enables to identify the vessels out of which fluid flows, and to estimate the amount of this fluid.

Another method of examining the retina is – optical coherence tomography (OCT). A special device scans the retina and forms detailed images of the retina and macula, and enables to measure the thickness of the retina and identify macular oedema.

How is macular oedema treated?

The best thing is to eliminate the cause of fluid leakage out of the vessels and retinal oedema. Treatment for macular oedema depends on the cause.

Intravitreal injections. There are the so-called vascular endothelial growth factor (VEGF) inhibitors which reduce the number of abnormal blood vessels in the retina, reduce fluid leakage and relieve retinal oedema. The medication is injected into the eye cavity with a very thin needle.

Steroids. If macular oedema is caused by inflammation, steroids can be used. Medications are used in the form of eye drops, tablets or injections into the eye cavity.

Eye drops. For treatment of cystic macular oedema after cataract surgery, ophthalmologists prescribe nonsteroidal anti-inflammatory medications in eye drops for several months.

Laser Laser . During the procedure, the ophthalmologist seals the damaged vessels with multiple laser pulses to stabilize vision.

Vitrectomy. If macular oedema occurs due to stretching the macula, vitrectomy is used – a surgical procedure to restore the normal (flat) configuration of the macula. The surgeon removes the vitreous from the eye cavity, as well as scar tissue from the macula, and fills the eye cavity with a gas bubble. Thus, the macula is freed from traction.

Sometimes, treatment results in increased pressure inside the eye. In this case, the ophthalmologist will prescribe an appropriate medication for you.

Macular oedema may go away within several months, depending on the cause and treatment. Be sure to follow the recommendations of your ophthalmologist for the treatment to be effective.

Outcomes

Macular oedema is swelling of the central area of the retina due to fluid build-up. Left untreated, macular oedema can lead to blindness. The symptoms of macular oedema include blurred vision, distortion of objects and faded colours. If you have these symptoms, see an ophthalmologist immediately. To treat macular oedema, injections and surgical treatment are used.

For questions about visual impairment, be sure to contact an ophthalmologist. The ophthalmologist will make every effort to protect and recover your vision.