Schizencephaly - Types, Causes, Symptoms, and Prognosis

Introduction:

People with schizencephaly may also have abnormally small heads, intellectual disability, partial or complete paralysis, and poor muscle tone. The symptoms depend on various factors, including the extent of the clefting and brain abnormalities. The exact cause of schizencephaly is unknown, but it has been known to be linked to genetic and non-genetic factors. The treatment includes physical therapy and medications to prevent seizures. In severe and complicated cases, a surgical procedure is done.

What Is Schizencephaly?

Schizencephaly refers to a rare congenital brain malformation in which abnormal slits or clefts are formed in the cerebral hemispheres of the brain. These clefts can appear on one or both sides of the brain. These hemispheres, which control language, motor skills, cognitive function, emotions, hearing, and vision. In schizencephaly, the clefts fill with cerebrospinal fluid and grey matter. While cerebrospinal fluid protects the brain from damage and grey matter helps regulate movement, memory, and emotions, excessive amounts in the clefts can lead to symptoms.

What Are the Different Types of Schizencephaly?

There are three different types of schizencephaly which include:

• Type 1: Type 1 is also known as trans-mantle schizencephaly. In this type, a cleft is created, which extends from one side of the brain to the other. It contains gray matter but does not contain fluid.

• Type 2: Type 2 is also known as closed-lip schizencephaly. This type occurs when the ridges are next to each other. In this type, the cleft is fused, and the fluid does not escape the area. Children with this type of schizencephaly present with hemiparesis or motor delay.

• Type 3: Type 3 is otherwise known as open lip schizencephaly. This causes a cleft where the ridges are separated. These clefts have fluid and gray matter. Patients with open lip schizencephaly present with hydrocephalus (raised pressure due to excessive fluid accumulation) or seizures. These types of schizencephaly can occur on one side of the brain or can appear on both sides of the brain. Unilateral clefts are more common than bilateral clefts.

What Are the Causes of Schizencephaly?

The exact cause of schizencephaly is not clear. It is considered that certain genetic changes can be responsible for the condition, but there can also be other causes. Genetic causes include changes in any of the four genes:

• EMX2.

• SIX3.

• SHH.

• COL4A1.

In rare cases, schizencephaly can affect more than one member of the family.

Around the eighth week in the womb, the brain cells start to move and form different areas in the brain. Damage to the blood vessels can cause problems with the development of cells and growth, resulting in birth defects.

Other causes that can contribute to the development of this condition include:

• Infections during pregnancy.

• Metabolic disorders.

• Alcohol consumption or drug use during pregnancy.

• Injury from amniocentesis.

What Are the Risk Factors for Schizencephaly?

Schizencephaly is less common, and the cause is still not clear, so it is hard to pinpoint the risk factors. Here are a few possible risk factors that can contribute to the condition:

1. Having certain genetic mutations.

2. Having a sibling, particularly an identical twin with this condition.

3. Exposure to certain infections before birth.

4. Taking certain medications that disrupt blood flow, for example, Warfarin.

5. Substance use disorder.

6. Viral infections, such as cytomegalovirus or Zika virus.

7. Low oxygen levels in the blood (hypoxia).

8. Amniocentesis.

9. Trauma.

10. Young maternal age, specifically having a child before age 25, can also elevate the risk.

What Are the Symptoms of Schizencephaly?

Schizencephaly is a congenital developmental disorder characterized by abnormal clefts in the cerebral hemispheres of the brain. Individuals with clefts in both hemispheres have the following symptoms:

• Seizures.

• Developmental delays.

• Delay in speech and language skills.

• Problems with brain-spinal-cord communication.

• Individuals with clefts in only one hemisphere have symptoms such as:

• Paralysis on one side of the body.

• Seizures.

Other signs and symptoms include:

• Abnormally small head (microcephaly).

• Hydrocephalus (raised pressure in the brain due to excessive accumulation of fluid in the brain).

• Intellectual disability.

• Partial or complete paralysis.

• Poor muscle tone (hypotonia).

How Is Schizencephaly Diagnosed?

Schizencephaly is diagnosed by computed tomography (CT) or magnetic resonance imaging (MRI). Both of these diagnostic tests can be used to determine brain abnormalities such as clefts or slits in the brain.

In some cases, schizencephaly can be diagnosed prenatally on ultrasound after 20 weeks of gestation. If clefting is detected on ultrasound, an MRI can be performed to confirm the diagnosis.

What Conditions Are Associated With Schizencephaly?

Healthcare professionals may identify schizencephaly in conjunction with other conditions such as cerebral palsy, agenesis of the corpus callosum, septo-optic dysplasia, and arachnoid cysts.

How Is Schizencephaly Treated?

There is no specific treatment for schizencephaly. The treatment mainly depends on the symptoms. However, seizures are the major symptom of schizencephaly, so anti-seizure medications are recommended. In severe cases, when the fluid builds up, a tube called a shunt is inserted to drain the fluid to other areas of the body where it can be absorbed and to keep the pressure off the brain.

The other treatment options include:

• Physical therapy - to improve the movement delays and to build muscle tone.

• Occupational therapy - to improve self-care and daily life skills.

• Speech therapy - to improve language and speech skills.

Can One Live a Normal Life With Schizencephaly?

Children who develop seizures as a result of a specific condition like schizencephaly can have lower survival rates than the normal population. Having seizures early in life can result in permanent behavioral abnormalities or disorders. And children with seizures that cannot be controlled are at higher risk for intellectual decline. There can be learning and language problems in a significant number of children with epilepsy. The progressive mental deterioration is often related to the neurological disorder that caused the seizures rather than the seizures themselves.

How Is the Prognosis of Schizencephaly?

The long-term prognosis of people with schizencephaly varies according to the size and location of the clefts and the extent of the intellectual disabilities. However, the symptoms can be managed with treatment. It can result in severe symptoms and disabilities or it can be relatively mild. This variability in symptoms means that individuals with schizencephaly may have normal lifespans but could also face complications. Controlling fluid levels and managing epilepsy are crucial aspects of treatment

Conclusion:

Schizencephaly is a rare congenital disorder, and there is no known cure for it. But there are treatments available to help manage the symptoms and improve the quality of life. You may require regular visits to the doctor and therapists to maintain good health and prevent complications.