Macular telangiectasia type 2

Macular telangiectasia (MacTel) type 2 is an eye disease affecting the macula that causes loss of central vision. MacTel develops when there are problems with the tiny blood vessels (capillaries) around the fovea, an area in the center of the macula where eyesight is the sharpest. In MacTel type 2, the capillaries around the fovea widen (become dilated) and leak. This causes fluid build-up and swelling, impairing reflection of light and causing progressive vision loss. As damage continues, new blood vessels may form, which can break and leak. This can lead to the development of scar tissue, further impairing central vision. MacTel type 2 affects both eyes and occurs most often in middle-aged adults.

Symptoms of MacTel type 2 can be subtle at first and may include slow loss of vision, distorted vision, blurring, trouble reading, and a spot of decreased or absent vision in the visual field. The vision loss in MacTel type 2 generally progresses over ten to twenty years (sometimes more). However, there may be periods when symptoms do not worsen, interspersed with episodes of sudden worsening of vision. MacTel type 2 usually does not cause total blindness, but vision loss can significantly impact quality of life.

The underlying cause of MacTel type 2 is not known (idiopathic). While it sometimes "runs in families" and may have a genetic component, no specific genes responsible for MacTel type 2 have been identified. Environmental factors may also play a role in the development of MacTel type 2. Some researchers believe that people with diabetes, hypertension, obesity, or other health problems may be at increased risk for developing MacTel type 2.

Vision loss associated with MacTel type 2 may be permanent. While no treatment has been proven to prevent progression, treatment may be helpful in some cases. Treatment options may include injection of anti-VEGF medications to limit the growth of new blood vessels, and the use of low vision aids.