Macular Telangiectasia - Eye Disease

An image of a healthy retina. UHB Trust

Macular telangiectasia, sometimes referred to as idiopathic juxtafoveal macular telangiectasia (and abbreviated MacTel), is a disease that affects the part of the eye called the macula, causing degradation or loss of central vision. The macula is the part of the retina, the light sensitive layer that lines the back of the eye. The macula allows us to have fine, detailed, clear central vision.

Macular telangiectasia causes disease within the tiny blood vessels that affect the center fovea, the center of the macula.

Types of Macular Telangiectasia

There are two types of macular telangiectasia, Type 1 and Type 2.

Type 1 macular telangiectasia, the less common form, usually affects only one eye. The blood vessels in the macula become dilated and form microaneurysms. Microaneurysms are small out-pouchings that occur in the blood vessels. Fluid can build up in the macular area causing swelling and loss of vision.

Type 2 macular telangiectasia is much more common. The blood vessels in the macula become dilated and leak fluid causing swelling and scarring which can lead to vision loss. Sometimes new blood vessels grow beneath the macula, affecting the macular photoreceptors and causing loss of vision. Type 2 tends to affect both eyes and both genders, as opposed to Type 1, which most often affects only one eye.

(Type 3 macular telangiectasia exists but is extremely rare. Patients with Type 3 tend to have more vessels diseased, causing the blood vessels to become occluded.)

Symptoms of Macular Telangiectasia

Patients with this condition may have it for years with little or no symptoms.  As the disease progresses, you may experience the following:

  • blurred vision
  • distorted vision
  • loss of central vision
  • skipping letters or words

Diagnosis of Macular Telangiectasia

Diagnosis of macular telangiectasia is made by first having a comprehensive eye examination.

Your eye doctor will perform an Amsler Grid test to determine if there are any distorted areas in your central vision. Your pupils will be dilated with special medicated eye drops so that the macula and retina can be visualized. He or she may also take digital retinal photographs. A special dye injection test called fluorescein angiography may also be performed to see how the blood circulates inside the retina. Finally, your doctor will perform an OCT or optical coherence tomography, a newer advanced way of analyzing the structure and anatomy of the macular area.

It is important not to confuse this disease with age-related macular degeneration. Although the symptoms can be be similar, they arise from different factors.

Treatment of Macular Telangiectasia

Because macular telangiectasia is considered a fairly rare condition, there is still much we don’t fully understand about it. We do know that some patients may only need careful monitoring and may not need treatment at all. If the blood vessels begin to leak fluid and cause swelling and scarring, doctors may use laser treatments to help relieve the swelling and reduce complication.

Steroids are sometimes used to quell inflammation, and newer drugs, such as anti-VEGF (vascular endothelial growth factor) drugs, are being used to stop abnormal blood vessel growth.

The MacTel Project

There is medical research underway called the MacTel project. The reason for this project is that the condition really has only been discussed for the last 25 years and there is not a lot of new information on the condition. Because it is a fairly rare disease, it is often missed by eye doctors. It is hoped that the MacTel project will shed new light on its clinical features, genetics, awareness, new treatments and support for people with the disease. Four hundred participants have been enrolled and are being examined annually, with relatives of the participants being screened as well.

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