Porencephaly

What is Porencephaly?

Porencephaly is a neurological disorder commonly caused by a cyst or cavity forming on the surfaces in the brain. In most cases, this results from the remains of lesions, but it is also possible for them to develop following an injury, trauma, infection or a lack of oxygen during pregnancy or childbirth. Porencephaly can affect children both before and after birth. Once the cysts have formed, it is possible for them to fill with cerebral fluid.

Porencephaly affects people in different ways and symptoms may range from mild to severe. In more severe cases, it is common for newborn babies to develop serious complications shortly after birth.

What causes porencephaly?

Porencephaly can be classified as familial or sporadic. In the case of familial porencephaly, genetics play a part and the condition is linked to defects linked to the COL4A1 gene. In the case of sporadic porencephaly, there are various possible causes, including:

• infection
• trauma and accidents that damage the brain or abdomen in a pregnant woman
• smoking and taking drugs during pregnancy
• haemorrhages and strokes
• complications during childbirth, including a lack of oxygen supply to the baby
• maternal diabetes

In very rare cases, porencephaly has been identified as a potential complication following antenatal testing, including chorionic villus sampling (CVS) and amniocentesis. These tests are often recommended if scans show abnormalities or there is a high risk of a baby being born with a birth defect or a congenital condition.

There is also evidence to suggest that disorders that increase the risk of bleeding in newborn babies may also increase the risk of porencephaly. This may be the case with issues such as deficiency in V Leiden or protein C.

Who is affected by porencephaly?

Both males and females can be affected by porencephaly. The exact number of cases is unknown and experts believe that some cases may go undiagnosed.

What are the symptoms of porencephaly?

Symptoms vary in severity and there can be significant differences between individuals. Some people may be mildly affected, while others will experience severe, life-limiting symptoms. Possible symptoms include:

• delayed development and growth
• lack of muscle tone (also known as hypotonia)
• seizures
• a smaller or larger head circumference than average
• delayed speech and language development
• paralysis (usually on one side of the body)
• stiff movement
• lack of flexibility
• delayed learning

Disorders related to porencephaly

Some disorders similar to porencephaly include:

• Arachnoid cysts: these fluid-filled cysts form on the arachnoid membrane, which is located on the brain and the spinal cord. It is possible for the cysts to grow and affect other parts of the brain. Sometimes, the cysts don’t cause any symptoms at all, while sometimes, they may result in headaches, seizures and hydrocephalus (when excess fluid collects on the brain).
• Cephalic disorders: cephalic disorders affect the development of the central nervous system and vary in type and severity. Examples include anencephaly, megalencephaly, schizencephaly and hydraencephaly.

How is porencephaly diagnosed?

Porencephaly can be diagnosed before and after birth. Tests used include CT and MRI scans. These scans produce very detailed internal images, which enable doctors to confirm a diagnosis.

What are the treatment options?

Treatment options for porencephaly include:

• medication to prevent and control seizures
• physiotherapy
• shunt treatment in cases of hydrocephalus
• speech and language therapy