What is macular telangiectasia (MacTel)?
Macular telangiectasia (MacTel) is a disease that affects the macula, causing central vision loss. It’s caused by abnormal blood vessels around the fovea. The fovea is the centre of the macula and is used for detailed central vision.
There are two main types of macular telangiectasia – type 1 and type 2. The blood vessel changes are different in each type.
Type 1 macular telangiectasia
In Type 1 macular telangiectasia, the blood vessels are dilated (enlarged) and aneurysms (or bulging of blood vessels) form. This causes swelling and damage to the macula. It usually occurs in one eye only and is believed to be a variation of Coats disease. Coats disease is a rare retinal disorder that most often impacts young people.
Type 2 macular telangiectasia
Type 2 is the most common form of macular telangiectasia. In Type 2, the blood vessels dilate (enlarge) and leak, causing swelling of the macula. Sometimes new blood vessels can form under the retina and also break or leak. Eventually, scarring over the macula can occur, severely affecting vision. This type of MacTel usually occurs in both eyes but can affect each eye differently.
Type 2 macular telangiectasia is typically diagnosed in people aged in their 40s and 50s. People with macular telangiectasia tend to have a higher prevalence of diabetes and high blood pressure.
Symptoms of MacTel
In its early stages, people with macular telangiectasia may not have symptoms. As the disease progresses over 10 to 20 years, there may be blurriness and distortion of central vision depending on the severity of the disease. Side or peripheral vision is usually unaffected.
How is MacTel diagnosed?
Signs of macular telangiectasia can be detected during a comprehensive eye examination by your optometrist or ophthalmologist. Your eye health professional may do further tests such as optical coherence tomography (OCT) and fluorescein angiography (FA) to confirm the diagnosis.
Unfortunately, there’s currently no effective treatment for macular telangiectasia.
In cases where new blood vessels have formed under the retina, your eye health professional may suggest injections of anti-vascular endothelial growth factor (anti-VEGF) into your eye to help prevent further vision loss.
The MacTel Project
The MacTel Project is an international study and registry program designed to improve the understanding and awareness of MacTel. It conducts patient-focused research and has an affiliated laboratory program.
The MacTel Project is coordinated by the Lowy Medical Research Institute and has more than 30 centres across the world, including in Australia. Please contact Macular Disease Foundation Australia for details of a participating centre near you.
Managing vision loss
If you experience vision loss as macular telangiectasia progresses, a key priority is maintaining quality of life and independence.