Congenital Glaucoma

What is congenital glaucoma?

Congenital glaucoma is a genetic form of glaucoma that’s either present at birth or develops during very early childhood. Glaucoma is any eye disease that damages the optic nerve in your eye, causing vision loss.

Children with congenital glaucoma have ocular hypertension (high pressure inside their eyes). The fluids in their eyes (aqueous humor) fail to drain normally, so they build up, raising the pressure inside. This puts stress on their optic nerves and can eventually cause structural changes to their eyes. You might notice that your child’s eyes appear enlarged, or that the darker parts appear pale and cloudy.

Congenital glaucoma is treatable, but without treatment, it can progress to blindness. It’s important to recognize and treat it as soon as possible to minimize the damage and vision loss it can cause.

What are the symptoms of congenital glaucoma?

The classic triad of symptoms includes:

• Epiphora (watery eyes, tearing).
• Photophobia (light sensitivity).
• Blepharospasm (uncontrollable eyelid twitching).

Other signs may include:

• Buphthalmos (enlarged eyeballs).
• Bluish discoloration of the eyeball.
• Whitening or clouding of the cornea.

You may or may not be able to tell that your child has vision issues, like:

• Blurry vision (astigmatism).
• Nearsightedness (myopia).
• Favoring one eye (anisometropia).

An eye exam might reveal further signs of glaucoma, like:

• Corneal edema (swelling).
• Tears in the cornea.
• Corneal scarring.

Children usually have signs and symptoms in both eyes. But sometimes, they appear only in one.

What causes congenital glaucoma?

Congenital glaucoma starts with a defect in the way your child’s eye develops. The most common defect is in their trabecular meshwork, the tissue that their eye fluids drain through. When this tissue doesn’t develop right, the fluids don’t drain properly. The buildup of fluids causes pressure in your child’s eye, which damages their optic nerve. It can also cause their cornea to enlarge, stretch, tear and scar.

This process is progressive. How fast it progresses depends on how severe the defect in your child’s eye is, how much fluid is building up and how high the pressure is. When glaucoma appears in young infants, it’s because these conditions were already progressing during fetal development. When symptoms appear later, it’s because these conditions were less severe at birth, so they took longer to build up.

Congenital glaucoma types

Healthcare providers often classify congenital glaucoma by the age when it first appears. Types include:

• Newborn (neonatal): apparent at birth or within the first month of life.
• Infantile: appears in the first two to three years of childhood.

Providers also classify congenital glaucoma by the type of defect that causes it (primary or secondary).

• Primary: occurs in isolation, without any other noticeable eye defects.
• Secondary (developmental): occurs with other defects as part of a diagnosed genetic disorder.

Researchers have identified several gene mutations that can lead to primary congenital glaucoma.

Specific genetic disorders that can cause secondary congenital glaucoma include:

• Aniridia.
• Axenfeld-Rieger syndrome.
• Sturge-Weber syndrome.

How is congenital glaucoma diagnosed?

Eye care specialists suspect congenital glaucoma when they see the classic signs and symptoms, especially in infants. To confirm it, they’ll give your child a complete eye exam under anesthesia. They’ll measure their intraocular pressure (tonometry) and the fluid drainage angle in their eye (gonioscopy).

Additional tests might include:

• Optical coherence tomography for a closer look at the optic nerve.
• Genetic testing for the gene variants that cause it.

What is the treatment for congenital glaucoma?

Most children with congenital glaucoma will need eye surgery to fix the defect that prevents their eye fluids from draining. Surgery is the standard treatment for congenital glaucoma, and it works best when it happens as early as possible. Medications also have a limited role to play. Your child’s provider might prescribe medications to use before or after surgery. Occasionally, medications are the only treatment needed.

Surgery

The main goal of surgery for congenital glaucoma is to reduce the intraocular pressure in your child’s eye. This reduces the stress on your child’s optic nerve and other structures. It prevents further damage and can even reverse some or all of the damage already done, depending on how soon your child starts treatment. Don’t worry — your child will be under anesthesia for eye surgery, so they won’t feel it.

Your surgeon will choose one of the following procedures, depending on your child’s age and condition:

• Goniotomy. Goniotomy means cutting into the drainage angle, the part of the eye that contains the trabecular meshwork that fluids drain through. Surgeons use a gonioscope to see their work.
• Trabeculotomy. When surgeons can’t see the drainage angle clearly through the cornea, they go around the back by cutting into the sclera with an electrocautery device called a trabeculotome.
• Trabeculectomy. If the above operations don’t work, a surgeon may approach the trabecular meshwork through the sclera and remove a section, creating a new tunnel for fluid drainage.
• Glaucoma drainage device. Your surgeon may implant a drainage device (a tube shunt) into your child’s eye. The shunt drains fluids onto a plate that sits just under their conjunctiva.

Medications

Medications can have side effects in young children, so healthcare providers prescribe them cautiously. Your provider might prescribe medications to help lower your child’s intraocular pressure or to improve the clarity of their cornea before surgery. This can help improve the results of surgery. Your provider might also prescribe medications to use during and after surgery to help prevent complications.

Medications might include:

• Beta-blockers.
• Diuretics.
• Prostaglandins.
• Alpha-adrenergic agonists.
• Antibiotics.
• Corticosteroids.
• Mitomycin.

What is the prognosis (outlook) for congenital glaucoma?

Surgery for congenital glaucoma is usually successful in reducing intraocular pressure and stopping the process that’s harming your child’s vision. Children who get treatment early and before too much damage has occurred can grow up to have relatively normal vision. But some vision loss may be irreversible, and some children may need additional treatment, such as corrective lenses.

Is congenital glaucoma preventable?

While congenital glaucoma can run in families, most cases are sporadic. Genetic testing can inform you of any gene mutations you might carry and your likelihood of passing them on. You can’t avoid passing your genes on to your children, but you can prepare for the possibility that your child might be born with a genetic disorder. For example, you can watch for the signs and be prepared to act quickly.