Aniridia (Absence of Iris)

Aniridia is a condition that causes babies to be born without irises (the colored part of your eye). Some babies are missing their entire irises. Others only have part of an iris in each eye.

Aniridia always affects both of your child’s eyes (it’s a bilateral condition).

A healthcare provider will probably diagnose aniridia when your child is born. They’ll be able to see the missing iris in your child’s eyes. No matter how much of your baby’s irises are missing, aniridia will affect their vision and can eventually lead to other issues in their eyes later in life.

Symptoms of aniridia

Because your child is missing their irises, their pupils will look larger than usual. Their pupils might be unevenly shaped. They’ll have a hard time adjusting to changes in lighting. This can lead to symptoms like:

• Blindness or partial vision loss in one or both eyes
• Blurry vision
• Eye pain
• Low vision
• Light sensitivity (photophobia)

What causes aniridia?

Aniridia is genetic disorder. It happens when a genetic change affects the PAX6 gene. This gene helps form your baby’s eyes and parts of their brain, spinal cord and pancreas. The genetic change that causes aniridia usually happens between the 12th and 14th week of pregnancy.

Risk factors

Aniridia is more common in children whose biological parents have it. If one parent has aniridia, there’s a 50/50 chance their biological child will, too.

So, if you have aniridia, that doesn’t guarantee that your biological children will have it. It just means they’re more likely to.

Aniridia can also happen on its own (sporadically) even if neither biological parent has it. This happens in around 1 in 3 cases.

Complications of this condition

Other parts of your child’s eyes might be underdeveloped, as well, including their optic nerves and retinas.

Children with aniridia are likely to develop other eye issues as they grow up, including:

• Cataracts
• Cloudy corneas
• Glaucoma
• Nystagmus

Children with sporadic aniridia have a higher risk of developing a Wilms tumor (a rare type of kidney cancer). The genetic change that causes sporadic aniridia is much more likely to impact other parts of your child’s body that the PAX6 gene is responsible for.

How is aniridia diagnosed?

Your provider will diagnose aniridia when your baby is born. You should be able to see the missing irises in your baby’s eyes.

If you’re pregnant and concerned about the fetus’s risk of aniridia (or other genetic disorders), talk to your provider about prenatal genetic testing. Your provider will use a blood test to tell how likely it is that the fetus could have a genetic disorder. They might also perform amniocentesis — removing and testing a small amount of your amniotic fluid.

How is aniridia treated?

Treating aniridia focuses on maintaining or improving your child’s vision.

Your child will need regular eye exams and visits with an eye care specialist. The sooner your provider diagnoses changes in your child’s eyes, the more likely they’ll be able to prevent symptoms or complications.

Your child might need a few treatments, including:

• Glasses or contact lenses. Just like anyone with vision issues, wearing glasses or contact lenses can improve your child’s vision. Kids with aniridia sometimes wear specialized colored contacts that mimic the shape of an iris to cover their pupils and reduce light sensitivity.
• Medications. If your child develops glaucoma or cornea issues, your provider might prescribe medicated eye drops, artificial tears or other medications.
• Surgery. Children who develop cataracts may need cataract surgery to remove them. Your child might also need glaucoma surgery. They might be able to get implanted artificial irises. This is a relatively new treatment, so not every child is a good candidate for this type of surgery.

When should I see my healthcare provider?

See a healthcare provider as soon as you notice any changes in your child’s eyes or vision. You might want to ask your provider questions like:

• How often will my child need eye exams?
• Is my child a good candidate for artificial iris surgery?
• What are the chances my child experiences complications?
• Which changes or symptoms should I look out for?

Go to the emergency room if your child has any of the following symptoms:

• A sudden loss of vision
• Severe eye pain
• Seeing new flashes or floaters in their eyes

What can I expect if my child has aniridia?

You should expect your child to have vision issues. Your child will need regular eye exams throughout their life to monitor their eye health.

More than 8 in 10 children with aniridia have poor or impaired eyesight. Most people with aniridia develop glaucoma, usually when they’re 10 to 20 years old.

But this doesn’t mean every baby born with aniridia will definitely face these issues. Talk to your provider or eye care specialist about what to expect as your child gets older.