Macular corneal dystrophy is a rare eye disease that causes clouding of the central part of your cornea. It’s a hereditary condition that’s passed through families with certain mutations in the CHST6gene.

Macular corneal dystrophy is a rare but severe form of corneal dystrophy. More specifically, it’s a type of stromal corneal dystrophy.

Corneal dystrophy is a group of conditions that cause opaque spots on your cornea. Your cornea is a layer of clear tissue that covers the front of your eye. Stromal corneal dystrophies are characterized by spots on your stroma, the thickest layer of your cornea.

Macular corneal dystrophy is a recessive genetic condition, meaning it only develops if you receive an associated gene from both birth parents. It leads to progressive haziness in your vision that can eventually progress to severe low vision.

Let’s take a deeper look at macular corneal dystrophy, including how it’s managed and the outlook for people with this condition.

Macular corneal dystrophy causes progressive loss of vision in both eyes due to clouding of your corneas. It’s symptomless in the early stages, but your degree of vision loss can become severe over time.

The age of onset varies, but vision loss often begins by the age of 10. Most people have severe vision loss by the age of 20 or 30.

Other signs and symptoms include:

Macular corneal dystrophy is caused by a recessive mutation in the gene CHST6. “Recessive mutation” means that you need to receive the mutation from both birth parents to develop the disease. Most other types of corneal dystrophy are dominant, meaning they develop when you receive an associated gene from only one birth parent.

More than 180 mutations in the CHST6 gene have been linked or possibly linked to macular corneal dystrophy.

Macular corneal dystrophy falls into a category of diseases called corneal dystrophies. These conditions affect fewer than 1 in 10,000 people in the United States.

More specifically, macular corneal dystrophy falls into a subcategory called stromal corneal dystrophies. In a 10-year study performed by researchers at McGill University in Montreal, researchers found that 27 of 93 (29%) of corneal dystrophies seen at their clinic over a 10-year period were stromal corneal dystrophies.

Macular corneal dystrophy only makes up a small percentage of stromal corneal dystrophies. In an older 2011 study, researchers estimated that it affects 9.7 per million people in the United States.

Macular corneal dystrophy can cause severe vision loss as it progresses due to the development of opaque spots on your cornea. It can also cause corneal ulcers, which can lead to difficulties like:

Symptoms of macular corneal dystrophy often start in childhood. It’s essential for your child to undergo regular eye exams to identify visual difficulties early.

The American Optometric Association recommends a comprehensive eye exam for children at the following frequencies:

AgeChildren at low riskChildren at high risk
Birth to age 2 yearsAt 6–12 monthsAt 6–12 months or as recommended
Age 3–5 yearsAt least once between 3–5 yearsAt least once between 3–5 years or as recommended
Age 6–17 yearsBefore first grade and annually afterBefore first grade and annually after, or as recommended

Doctors can diagnose corneal dystrophy with a comprehensive dilated eye examination. During this examination, a doctor will use a microscope with a bright light called a slit lamp to check your eyes for characteristic signs of the disease.

No medical therapy has been developed to slow the progress of macular corneal dystrophy. Researchers are investigating gene replacement therapy, which involves delivering the missing gene to cells in your cornea.

A cornea transplant, or keratoplasty, may help improve vision. In a 2021 study, researchers reported postoperative vision better than 20/40 in 90.9% of 22 eyes treated with deep anterior lamellar keratoplasty and 76.3% of 135 eyes treated with penetrating keratoplasty. Both groups had more than 90% graft survival after at least a year.

Some small studies suggest that a type of laser therapy called phototherapeutic keratectomy may help improve vision temporarily, but symptoms almost always come back within months.

Macular corneal dystrophy often leads to severe loss of vision by your 20s or 30s. You may be able to relieve some of your symptoms with treatments, such as:

Macular corneal dystrophy is a genetic condition. There’s no known way to prevent it.

Here are some frequently asked questions that people have about macular corneal dystrophy.

How serious is corneal dystrophy?

Macular corneal dystrophy can lead to severe loss of vision. Most people have serious vision loss by their 20s or 30s.

Does macular dystrophy cause blindness?

Macular dystrophy can lead to blindness when the disease progresses to an advanced stage.

How fast does corneal dystrophy progress?

Macular corneal dystrophy usually onsets before the age of 10 and usually causes severe vision loss 10–20 years later.

What’s the difference between macular and granular corneal dystrophy?

Granular corneal dystrophy is a type of epithelial-stromal dystrophy and also affects the outermost layer of the cornea. It usually causes vision loss in your 40s.

Macular corneal dystrophy doesn’t have a cure, but symptoms can be managed with treatments such as eye drops and ointment. A corneal transplantation may help improve vision by removing the cloudy spots on your cornea.