Encephalocele

What is encephalocele?

Encephalocele (pronounced “en-SEF-al-oh-SEEL”) is a birth defect that causes brain tissue to grow through an opening of your baby’s skull. This condition is a neural tube defect. The neural tube is the early form of the brain and spinal cord when the fetus is developing in the uterus. If there’s a problem with how the top of the neural tube closes during the first few weeks of pregnancy, encephalocele can happen. This condition can range from mild to life-threatening.

Types of encephalocele

The types of encephalocele identify the location of the opening in the skull:

• Occipital: The lower back of your baby’s head.
• Parietal: Top, nearest the back of your baby’s head.
• Frontoethmoidal (also called sincipital): Near your baby’s forehead.
• Sphenoidal: Front-middle or behind your baby’s eyes and in front of their ears.

In addition, you may hear your child’s healthcare provider mention two broader categories of encephalocele:

• Anterior: Front of your child’s skull.
• Posterior: Back of their skull.

How common is encephalocele?

Encephalocele is rare. An estimated 1 in 10,500 babies are born with the condition in the United States. Each year, this equals about 375 babies born in the U.S.

What does encephalocele look like?

A newborn with encephalocele will have a gap in their skull that isn’t closed. This causes a bulge or sac of brain tissue covered in skin coming out of the skull opening. This can look similar to a balloon coming out of your child’s head. Depending on where the skull opening is, the skin on the sac may have hair on it.

The skull opening can happen anywhere on their head. It’s most common on the forehead or the lower back of their head near the base of your baby’s skull.

What are the signs and symptoms of encephalocele?

Signs and symptoms of encephalocele include:

• Headache.
• Visual problems.
• Muscle weakness in arms and legs.
• A smaller-than-expected head size at birth.
• Uncoordinated movements (ataxia).
• Facial malformations.
• Nasal obstruction.
• Spinal fluid leaking from nose or ear.

Symptoms vary based on the size and location of the skull opening and how much brain tissue is outside of the skull at birth. Symptoms can be associated with fluid buildup in the brain (hydrocephalus).

What are the complications of encephalocele?

Some cases of encephalocele have few to no complications. Long-term complications could include:

• Developmental delay.
• Problems with cognitive development (intellectual disability).
• Vision issues.
• Delayed growth.
• Seizures.

What causes encephalocele?

Most encephaloceles are congenital (meaning you’re born with it), but some can be acquired as a result of trauma, tumor or other rare conditions such as idiopathic intracranial hypertension.

Congenital encephaloceles form when there’s an issue with how the top of the neural tube closes. The neural tube is a piece of tissue that’s the early version of the brain and spinal cord. It forms the shape of a tube during the third and fourth weeks of pregnancy. The neural tube should fold and close during embryonic development. If the top part of the tube doesn’t close as expected during this time, the skull doesn’t close completely. As a result, part of your baby’s brain grows out of this opening in the skull.

The exact reason why the neural tube doesn’t close completely is unknown. Research suggests it could be the result of:

• A genetic change that happens during conception.
• An infection (toxoplasmosis, rubella, cytomegalovirus, herpes simplex virus).
• A neurological (brain or nerve) condition (like type 3 Chiari malformation).

An underlying medical condition may lead to encephalocele. These conditions include:

• Walker-Warburg syndrome.
• Knobloch syndrome.
• Roberts syndrome.
• Amniotic band syndrome.

What are the risk factors for encephalocele?

You’re more likely to have a child with encephalocele if you have a history of neural tube defects (NTD) in your biological family history. You’re also more likely to have a child with an NTD if you don’t get enough folic acid (vitamin B9) before and during pregnancy.

How is encephalocele diagnosed?

Your healthcare provider can diagnose encephalocele at a routine ultrasound during pregnancy. Your provider may order a prenatal MRI imaging test to learn more about the birth defect during pregnancy.

Confirmation of the diagnosis happens immediately after your baby is born based on a visual examination of your baby. Further blood and imaging tests may help diagnose an underlying cause or let your child’s healthcare provider understand how the condition affects your baby so they can treat it.

Can encephalocele go undiagnosed?

Yes, small encephalocele openings in the skull may go undiagnosed. These usually happen near your baby’s nose or forehead. Small encephalocele openings don’t usually cause symptoms that affect your newborn or complications that affect them as they grow.

How is encephalocele treated?

Treatment for encephalocele is surgery to repair the skull and remove brain tissue that grew outside of the skull. Often, the portion of the brain that’s outside of the skull isn’t functional and can be removed. When the opening is small, sometimes, the brain can be gently moved back into the skull before a surgeon repairs the skull.

Treatment usually happens shortly after birth or within the first few months to a year, depending on the size, location and effects the condition has on your baby.

Children usually need more than one surgery to treat this condition. Surgery can also treat facial growth irregularities and hydrocephalus.

As your child grows, they may need additional support to treat associated conditions like:

• Special education programs in school.
• Medications for seizures.
• Glasses for vision problems.

Are there side effects of the treatment?

Each surgery comes with possible side effects. Your baby’s care team is highly trained to prevent or reduce your child’s risk of complications during and after surgery.

Risks include:

• Infection.
• Spinal fluid leak.
• Bleeding.

When the opening is larger and involves more brain tissue, there’s a higher risk of neurological issues.

Talk to your child’s healthcare provider about the side effects of treatment before it begins.

Can encephalocele be prevented?

There’s no known way to prevent encephalocele. You can reduce your risk of having a child with a neural tube defect by getting plenty of folic acid.

Talk to your healthcare provider before you plan on becoming pregnant. They may recommend you take 400 mcg of folic acid daily, even if you don’t plan to get pregnant right away. Neural tube defects (NTDs) happen in the first month of pregnancy. This is often before you even know you’re pregnant, which is why it’s essential to start taking folic acid early.

In addition, let your healthcare provider know if you have a family history of NTDs or if you had a child with an NTD. Your provider can help you prevent future NTDs.

Can babies survive encephalocele?

Yes, babies can survive encephalocele. Treatment with surgery to repair the skull can help them survive. Babies with large skull openings may have more symptoms and complications than babies with smaller openings. This increases their risk of life-threatening outcomes or a shorter life expectancy.

Studies found that newborns with skull openings near the front of their heads have a better outcome than babies with openings in the back of their heads.

What is the mortality rate of encephalocele?

The U.S. Centers for Disease Control and Prevention (CDC) estimates the mortality (death) rate for large encephalocele is 45%. That means that the survival rate is 55%. The risk of life-threatening complications increases due to the size and location of the skull opening and the overall health of your baby at birth.

When should I see a healthcare provider?

If you’re planning to become pregnant, talk with a healthcare provider about preconception counseling. They can help you maintain good health to lower your risk of having a child with a birth defect.

What questions should I ask my healthcare provider?

• Where is the skull opening on my newborn?
• Does my child need surgery?
• What are the side effects of surgery?
• How do I take care of my child after surgery?
• What complications should I look out for?
• What do I do if my child misses developmental milestones for their age?