What Is Macular Telangiectasia?

Macular telangiectasia, sometimes referred to as idiopathic juxtafoveal macular telangiectasia, is a disease that affects the part of the eye called the macula, causing degradation or loss of central vision.

The macula is part of the retina, the light-sensitive layer that lines the back of the eye. The macula allows us to have fine, detailed, and clear central vision.

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

Types

There are three types of macular telangiectasia: Type 1, Type 2, and Type 3.

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

Type 2 macular telangiectasia, sometimes abbreviated as MacTel2, is much more common. With Type 2, 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 people of all sexes, with a slight female preponderance, as opposed to Type 1, which most often affects only one eye and is congenital.

Type 3 macular telangiectasia is extremely rare. People with Type 3 tend to have more diseased vessels, causing the blood vessels to become occluded.

Symptoms

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

Diagnosis

Diagnosis of macular telangiectasia is made by having a comprehensive eye examination. Your eye healthcare provider 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. The eye doctor 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. This is used to check if the vessels affected by MacTel are leaking fluid into the retina.

Finally, your healthcare provider will perform an optical coherence tomography, a newer, more 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 similar, they arise from different factors.

Treatment

Because macular telangiectasia is considered a fairly rare condition, there is still much we don’t fully understand. We do know that some patients may only need careful monitoring and may not need treatment.

If the blood vessels begin to leak fluid and cause swelling and scarring, healthcare providers may use laser treatments to help relieve the swelling and reduce complications. Steroids are also 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. Because it is a fairly rare disease and has only been discussed during the last 25 years, it is often missed by eye healthcare providers. 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.