Macular Telangiectasia

Macular telangiectasia, or MacTel, is a disease that damages the central part of your vision, affecting your ability to read, drive, and recognize faces. While it’s a rare condition, understanding what happens in your eyes can help you manage the disease and maintain your quality of life.

Table of contents

• What is macular telangiectasia?
• Different types of MacTel
• Recognizing the symptoms
• What causes MacTel?
• How doctors diagnose MacTel
• Current treatment options
• Living with MacTel
• Research and new treatments

What is macular telangiectasia?

Macular telangiectasia is a disease that affects the macula, which is the central part of your retina — the light-sensing tissue at the back of your eye^[1]. The condition specifically damages blood vessels around the fovea, which is the very center of the macula responsible for sharp, detailed vision^[1][6].

When you have MacTel, tiny blood vessels near the fovea become swollen, enlarged, and twisted^[5]. These abnormal blood vessels are more prone to leaking fluid, which causes swelling in the retina known as macular edema^[2][7]. Over time, this damage affects your ability to see things directly in front of you.

Although MacTel was previously thought to be mainly a problem with blood vessels, recent research suggests it is actually a neurodegenerative disease^[4]. This means that certain cells in your retina, particularly Müller cells that support and maintain retinal health, become damaged and can no longer work properly^[4][13]. As these supporting cells die off, the light-sensing cells in your retina go with them.

Experts estimate that about 2 million people worldwide have this condition, though the actual number might be higher because MacTel can be confused with more common eye diseases^[5][2].

Different types of MacTel

There are two main types of macular telangiectasia, and they affect people differently.

MacTel Type 1 occurs when blood vessels in the eye enlarge and bulge, creating small aneurysms (areas where blood vessel walls swell)^[2][5]. This type usually affects only one eye and is believed to be related to Coats disease, a rare eye disorder that most often affects young men^[2][5]. When fluid leaks from these abnormal vessels, it leads to swelling in the macula.

MacTel Type 2 is by far the most common form of the disease^[2][4]. With this type, blood vessels in the macula become dilated and leak, causing damage to the central retina^[2]. Unlike Type 1, MacTel Type 2 usually affects both eyes, though each eye may progress at different rates or show different levels of severity^[2][4]. Most people are diagnosed with Type 2 in their 40s and 50s, though the disease has likely been progressing for many years before symptoms appear^[4][5].

There is also a MacTel Type 3, but it is extremely rare and not well understood^[5].

Recognizing the symptoms

In the early stages of MacTel, you may not notice any problems with your vision^[5]. However, as the disease advances over time, you will likely experience changes that affect your central vision.

Common symptoms include:

• Blurred or distorted vision in the center of your visual field^[5][2]
• Difficulty reading as letters or words seem to disappear^[8][23]
• Straight lines appearing wavy or distorted^[5]
• Trouble seeing well in low-light conditions or at night^[5]
• Small blind spots, called scotomas, that develop near the center of your vision^[5][23]
• Slower reading speed as your eyes struggle with letters falling into blind spots^[23]

These symptoms typically develop gradually over many years — sometimes 10 to 20 years^[5]. The disease causes a slow loss of about one letter of vision each year^[23]. MacTel does not affect your peripheral (side) vision and rarely leads to complete blindness^[2][5].

As the disease progresses, everyday tasks like reading, writing, driving, and seeing people’s faces become increasingly difficult^[1][5]. Many people with MacTel also feel anxious about driving because they lose confidence in their ability to see vehicles and other road hazards^[23].

What causes MacTel?

Scientists don’t know exactly what causes macular telangiectasia^[5]. However, research has provided several important clues about how the disease develops.

The most current understanding is that MacTel Type 2 begins with dysfunction of Müller cells, which are essential for maintaining the structure and health of your retina^[4][10]. One of the key jobs of these cells is to produce a protein called ciliary neurotrophic factor (CNTF), which supports the normal function of light-sensing cells in your retina^[23]. When Müller cells die off, photoreceptors and other retinal cells are lost as well, and the blood vessels in the area become abnormal^[4][23].

Genes may play a role in who develops MacTel. The condition can run in families, suggesting a genetic link, although scientists have not identified specific genes responsible for the disease^[2][5]. MacTel is most commonly diagnosed in middle-aged adults, and it affects men and women about equally^[4].

Some health conditions may increase your risk. High blood pressure and diabetes can affect the health of blood vessels in your eyes and alter retinal metabolism^[2]. Maintaining good control of your blood pressure and blood sugar may help protect your eye health.

How doctors diagnose MacTel

Diagnosing MacTel can be challenging because it is a rare disease that can be mistaken for more common conditions like age-related macular degeneration or diabetic retinopathy^[2][8]. Getting an accurate diagnosis is important so you can receive appropriate care and support.

During an eye examination, your doctor may notice several characteristic signs of MacTel. These include a grayish appearance of the retina near the macula, small crystal deposits, changes in pigmentation, and unusually shaped blood vessels^[8][23].

To confirm the diagnosis, your doctor will likely use several imaging tests:

Fluorescein angiography involves injecting a special dye into your arm and taking photographs as it travels through the blood vessels in your eye^[8][23]. This test shows the characteristic widening and leaking of blood vessels around the fovea that gives MacTel its name.

Optical coherence tomography (OCT) uses light waves to create detailed cross-sectional images of your retina^[8][23]. In MacTel, OCT reveals small cavity-like spaces in the retina where cells have been lost, breaks in the layer of light-sensing cells, and disorganization of retinal tissue^[8].

Fundus autofluorescence imaging shows areas of increased or decreased natural fluorescence in the retina, which helps identify damaged areas^[8].

These imaging studies are especially helpful for diagnosing MacTel early, when findings on standard eye examination may be subtle^[8].

Current treatment options

For many years, there was no approved treatment for macular telangiectasia. However, the treatment landscape has recently changed with the approval of a new therapy, and research continues into additional options.

In March 2025, the U.S. Food and Drug Administration approved revakinagene taroretcel-lwey (Encelto) as the first treatment for MacTel Type 2^[9][10]. This is a tiny implantable device, about the size of a grain of rice, that uses encapsulated cell therapy (ECT) to deliver therapeutic amounts of CNTF directly to the retina^[9][10].

The device contains approximately 300,000 genetically modified cells that continuously produce CNTF through a semi-permeable membrane^[10]. It is surgically placed into the eye and anchored to the outer wall, where it can function for more than a decade, possibly indefinitely^[10]. In clinical trials, this treatment reduced the rate of photoreceptor loss by about 55% over two years and also slowed the decline in reading speed by up to 69%^[10]. The treatment is expected to be available to patients starting in June 2025^[9][10].

For the proliferative phase of MacTel, when abnormal new blood vessels grow under the retina causing rapid vision loss, doctors use anti-VEGF injections^[4][11][13]. These medications help stop the growth and leakage of abnormal blood vessels. Anti-VEGF drugs have been shown to provide significant structural and functional improvement when neovascularization develops, though they do not help the non-proliferative phase of the disease^[11][13].

Some other approaches have been studied but with mixed results. Carotenoid supplementation and oral acetazolamide showed some structural improvements but without accompanying functional benefits^[11]. Laser treatment has generally been found ineffective for treating MacTel^[2].

Living with MacTel

While MacTel presents challenges, there are many practical strategies that can help you manage daily life and maintain your independence.

For reading and close work, try using a ruler under the lines to help maintain focus^[17]. Adjust text size on your computer and phone to make reading more comfortable and reduce eye strain^[17]. Take regular breaks from screens to rest your eyes when feeling strained^[17].

Control the lighting in your environment, making it brighter or dimmer as needed for your comfort^[17]. Some people find that yellow-tinted glasses help enhance color contrast and block blue light from screens^[17]. For viewing events from a distance, binoculars can be helpful^[17].

If driving becomes uncomfortable, especially at night, it’s important to avoid it for your safety and that of others^[17]. Consider other transportation options or ask family and friends for help.

Staying connected with friends and family is crucial for your emotional well-being. Communicate openly about how you’re doing and what challenges you face^[17]. You can also find MacTel communities on social media for additional support from others who understand what you’re going through^[17].

Low vision specialists can provide additional tools and strategies to help you adapt to vision changes. These professionals can recommend magnifiers, special lighting, and other assistive devices tailored to your needs.

Research and new treatments

Research into macular telangiectasia continues to advance our understanding of the disease and potential treatments.

The Lowy Medical Research Institute (LMRI) is a non-profit organization dedicated to the study of MacTel^[2]. LMRI sponsors clinical and laboratory research, including the MacTel Project, which is a natural history study and registry of MacTel patients^[2]. More than 60 centers around the world participate in this project, making the search for information a global effort^[2]. By enrolling in the MacTel Project Registry, patients help advance MacTel research and may have the chance to participate in clinical research^[2].

The encapsulated cell therapy platform that led to the first approved treatment for MacTel could potentially be adapted to deliver other therapeutic proteins for a range of retinal conditions^[10]. This technology represents a promising new approach to treating chronic eye diseases by providing long-term, sustained delivery of protective factors directly to the retina.

Scientists continue to investigate the underlying causes of MacTel, including the role of metabolic factors and genetic risk factors. Understanding these mechanisms may lead to additional treatment approaches in the future.

idiopathic juxtafoveal telangiectasis, perifoveal telangiectasia, juxtafoveal telangiectasis