Dandy-Walker Syndrome

Dandy-Walker syndrome, also known as the Dandy-Walker malformation, is a rare, congenital hydrocephalus (a buildup of fluid in the brain) that affects the cerebellum portion of the brain. The condition, which occurs in one in every 25,000 to 35,000 live births each year, causes different parts of the cerebellum to develop abnormally.

Some malformations associated with Dandy-Walker syndrome include:

• The absence or limited development of the vermis, the central part of the cerebellum
• Limited development of the left and right sides of the cerebellum
• An enlargement of the fourth ventricle, a small space that allows fluid to flow between the upper and lower portions of the brain and the spinal cord
• The development of a large, cyst-like formation at the base of the skull, where the brainstem and cerebellum are located

The degree of this condition and its effects vary from person to person but can require lifelong management. Read on to learn more about Dandy-Walker syndrome, as well as its causes, symptoms, and treatment options.

Dandy-Walker Syndrome Causes

The development of Dandy-Walker syndrome occurs very early in utero when the cerebellum and its surrounding structures fail to fully develop.

Although many people with Dandy-Walker syndrome have chromosomal abnormalities linked to the condition, researchers believe most cases are caused by highly complex genetic components or isolated environmental factors, like exposure to substances that cause birth defects.

Immediate family members, like children or siblings, are at an increased risk of developing Dandy-Walker syndrome, but it doesn’t have a distinct inheritance pattern—for siblings, the occurrence rate hovers around 5%.

Some research suggests that the health of the mother may also contribute to the development of Dandy-Walker syndrome. Women with diabetes are more likely to give birth to a child with the condition.

What Are the Symptoms of Dandy-Walker Syndrome?

For most people, the signs and symptoms of Dandy-Walker syndrome are evident at birth or within their first year, but 10 to 20% of individuals may not develop symptoms until late childhood or early adulthood.

Symptoms of Dandy-Walker syndrome vary from person to person, but developmental troubles in infancy and increased head circumference due to hydrocephalus may be the first—or only—signs.

Because the cerebellum is a vital part of the body’s movement, balance, and coordination, many people with Dandy-Walker syndrome have issues with their voluntary muscle movements and coordination. They may also experience difficulties with motor skills, mood, and behavior, and can have limited intellectual development. About half of those with Dandy-Walker syndrome have intellectual disability.

Common symptoms of Dandy-Walker syndrome include:

• Slowed motor development: Kids with Dandy-Walker syndrome often experience delays in motor skills like crawling, walking, balancing, and other motor skills that require the coordination of body parts.
• Progressive enlargement of the skull and bulging at its base: Buildup of fluids in the skull can increase the size and circumference of the skull over time, or cause a large bulge to develop at its base.
• Symptoms of intracranial pressure: The buildup of fluids can also contribute to increased intracranial pressure. Although these symptoms are hard to detect in babies, irritability, bad mood, double vision, and vomiting may be indicators in older kids.
• Jerky, uncoordinated movements, muscle stiffness, and spasms: The inability to control movements, balance, or perform coordinated tasks may suggest issues with the development of the cerebellum.  
• Seizures: Approximately 15 to 30% of people with Dandy-Walker syndrome experience seizures.

If your child begins to develop any of these symptoms, contact your pediatrician immediately. Be sure to record your child’s symptoms, when they started, the severity of symptoms, and any noticeable progression, and bring your notes to your appointment.

How Is Dandy-Walker Syndrome Diagnosed?

Dandy-Walker syndrome is diagnosed with diagnostic imaging. After a physical exam and questionnaire, your child’s healthcare provider will order an ultrasound, computed tomography (CT) scan, or magnetic resonance imaging (MRI) to look for signs of Dandy-Walker syndrome, including malformations in the brain and the buildup of fluids.

Treatment for Dandy-Walker Syndrome

Although Dandy-Walker syndrome can interfere with everyday life, milder cases don’t always require treatment—it depends on the severity of the developmental and coordination issues the person is experiencing.

Some common treatments for Dandy-Walker syndrome include:

• The surgical implantation of a shunt in the skull: If your child experiences increased intracranial pressure, doctors may recommend inserting a shunt (a small tube) in the skull to help alleviate pressure. This tube will drain fluid from the skull and carry it to other areas of the body, where it can be safely absorbed.
• Various therapies: Special education, occupational therapy, speech therapy, and physical therapy can help your child manage the issues linked to Dandy-Walker syndrome. Talk to your pediatrician about the therapies that will be most effective for your child.

Survival and prognosis depend on the severity of the malformation and the presence of other congenital defects. Life expectancy associated with Dandy-Walker syndrome increases exponentially the older the child becomes.

Summary

Dandy-Walker syndrome is a congenital condition that causes a buildup of fluid in the brain and abnormal development in the cerebellum. Researchers believe most cases are caused by highly complex genetic components or isolated environmental factors.

Survival and prognosis depend on the severity of the malformation and the presence of other congenital defects. However, most people with Dandy-Walker syndrome can lead happy, healthy lives with the help of educational, occupational, and physical therapies.