Porencephaly

What is porencephaly?

Porencephaly is a rare disorder usually diagnosed before birth or during infancy. Damage to the cerebral hemispheres in your child’s brain can happen either during pregnancy or shortly after birth. This damage leads to the development of fluid-filled cavities, called cysts, in their brain.

The cysts can interfere with normal brain growth and development. Children with porencephaly may experience speech difficulties. They may also have other neurological deficits (abnormal functioning in areas of their body).

How common is porencephaly?

Porencephaly is an extremely rare disorder. Experts don’t know exactly how many children have it. The disorder affects all genders equally.

What are the different types of porencephaly?

There are two types of porencephaly:

• Acquired: This is the more common form. It results from damage to your child’s developing brain.
• Genetic: In very rare cases, porencephaly results from a genetic mutation.

What causes porencephaly?

In genetic porencephaly, harmful changes (mutations) can occur in certain genes (COL4A1 or COL4A2). These genes are important for producing certain types of proteins that provide structural support to many tissues in your body. Mutations in these genes can disrupt the structure of tissues, leading to abnormalities like cysts in your brain.

In acquired porencephaly, stroke or infection interferes with the normal blood flow to your child’s brain and can cause a lack of oxygen or bleeding. The injury can occur before, during or soon after birth.

With a lack of oxygen or bleeding in your child’s brain, fluid-filled cysts can replace normal brain tissue. This is more likely to happen if the following risk factors are present:

• Alcohol or drug use during pregnancy.
• Gestational diabetes.
• Infection during pregnancy.
• Infection shortly after birth.
• Trauma during birth.
• Other causes of stroke or lack of oxygen to their brain (like blood disorders and metabolic diseases).

Sometimes, healthcare providers can find clues about the underlying cause based on the location, size and distribution of the cysts.

What are the symptoms of porencephaly?

Symptoms and signs of porencephaly vary in how severe they are and when they first appear. Neurological deficits (abnormal functioning in the body) depend on where the brain cysts develop and how big they are. This isn’t all that different from what happens with a stroke. Symptoms may include:

• Speech and language delays.
• Delayed physical development.
• Delayed cognitive development.
• Delayed social development.
• Enlarged or small head relative to body size.
• Low muscle tone (hypotonia).
• Weakness.
• Problems processing sensory information.
• Seizures.

What are the complications of porencephaly?

In some cases, porencephaly can block the cerebrospinal fluid (CSF) that surrounds your child’s brain and spinal cord. This leads to a backup of fluid, which adds pressure around their brain (known as hydrocephalus). If the pressure becomes high enough to put pressure on their brain itself, then existing symptoms can worsen or new symptoms might arise. New symptoms may include headaches, vomiting and vision problems.

Since porencephaly can cause seizures, children with porencephaly are more likely to develop epilepsy. Some can also have muscle spasticity, when their muscles overly tighten and contract.

How is porencephaly diagnosed?

Children with porencephaly usually show signs of the condition shortly after birth. Most receive a diagnosis before their first birthday. Sometimes, the brain cysts are visible on a prenatal ultrasound. Your healthcare provider may be able to diagnose the condition before your baby is born.

To confirm a diagnosis of porencephaly, your healthcare provider needs to see detailed images of your child’s brain. You or your child may have imaging tests like:

• Prenatal ultrasound or ultrasound.
• CT scan.
• MRI.

How is porencephaly managed or treated?

There’s currently no cure for porencephaly, but there are many ways to manage its effects. Treatments focus on improving neurological impairments. If hydrocephalus is present, excess fluid around your child’s brain can be drained.

Possible therapies may include:

• Anti-seizure medication.
• Medication to improve muscle tightness.
• Medication to reduce pain.
• Physical therapy.
• Speech therapy.
• Occupational therapy.
• Surgery to remove a cyst.
• Surgery to drain excess cerebral fluid.

Can porencephaly be prevented?

Porencephaly can’t always be prevented. But having a healthy pregnancy may reduce your child’s risk.

During pregnancy, it’s important not to misuse alcohol or drugs. If you have gestational diabetes, follow your healthcare provider’s guidance for managing the condition.

Genetic porencephaly can sometimes be inherited if just one parent carries the mutated gene. Genetic testing can determine if you or your partner carry the gene. A genetic counselor can help you understand the risks of passing this gene to your child.

What is the prognosis (outlook) for people with porencephaly?

Some children with porencephaly experience neurological problems. Others show no problems whatsoever. The severity of these symptoms varies widely. The outlook depends on the size, location and number of brain cysts and how they affect each individual child.

When should I call the doctor?

You should call your healthcare provider if your child experiences new or worsening:

• Headaches.
• Vomiting.
• Problems with balance or coordination.
• Seizures.
• Paralysis of any part of their body.
• Vision changes.

What questions should I ask my doctor?

You may want to ask your healthcare provider:

• What are the chances of having another child with porencephaly?
• Should my family have genetic testing?
• Will my child need surgery to remove cysts or excess fluid from their brain?
• What are the best therapies to help my child cope with developmental delays?

A note from Cleveland Clinic

Porencephaly is a very rare disorder. Children with this condition can experience mild-to-severe physical and cognitive disabilities. With early intervention and therapy, many children with porencephaly can lead full, productive lives.