Dandy-Walker Syndrome

There are four types of Dandy-Walker syndrome, each affecting different portions of the skull in different ways:

• Dandy-Walker malformation: affects the fourth ventricle and a large posterior fossa
• Dandy-Walker variant: affects the fourth ventricle and normal posterior fossa
• Mega cisterna magna: affects the large posterior fossa, normal vermis and fourth ventricle
• Posterior fossa arachnoid cyst: affects the posterior fossa, a small piece of the skull near the brainstem, responsible for balance and coordination

Dandy-Walker syndrome is a genetic mutation creating an issue with the development of the baby’s cerebellum while developing in the mother’s uterus. The cause is often the result of a chromosomal condition, including extra or missing parts of chromosomes.

The cause of Dandy-Walker syndrome is primarily genetic factors, and more common in mothers who have diabetes. There are some studies that also link maternal age, and a history of infertility increases chances of this congenital malformation.

As with most genetic malformations, screening the mother using an ultrasound test can detect problems with how the baby’s brain is forming. Additionally, fetal MRI scans are a noninvasive test that allows doctors to get a more detailed image of the baby’s organs.

Those with Dandy-Walker syndrome will display a range of symptoms depending on their age and stage of development. 

Symptoms of Dandy-Walker syndrome in babies:

• Slow development of motor skills (the ability to control movements)
• Progressive growth of the skull

Symptoms of Dandy-Walker syndrome in older children:

• Pressure in the skull
• Irritability
• Throwing up
• Having a hard time with balance or controlling muscle movements
• Unusual eye movements

Dandy-Walker syndrome can cause unusual development of the head, heart, face, arms or legs—although some children may never have symptoms. Treatment focuses on symptoms. Surgery may help get rid of extra fluid that causes some of the symptoms, and physical and other forms of therapy can help with managing symptoms.

A doctor will do a thorough physical exam as well as an ultrasound. If there are any abnormalities detected, additional scans may be ordered, including a computed tomography scan (CT), or a magnetic resonance imaging (MRI).

Treatment depends on the severity of the malformation. Mild cases of Dandy-Walker syndrome won’t always require treatment. For more serious cases with obvious symptoms, treatment options may include:

• Speech therapy
• Occupational therapy
• Special education
• Surgical implantation of a shunt in the skull to reduce pressure

Many children diagnosed with Dandy-Walker syndrome will initially need extensive medical care at the time of birth, but have low incidents of long-term effects and are able to live normal lives. In more severe cases that involve paralysis, seizures and developmental delays, additional care may be required. Work with your pediatrician and primary care physician to form a team of experts that may include physical and occupational therapists.

To further your understanding of your diagnosis and to contribute to cutting-edge research, consider participating in a clinical trial so clinicians and scientists can learn more about causes, symptoms, treatment and prevention. Clinical research uses human volunteers to help researchers learn more about a disorder and perhaps find better ways to safely detect, treat or prevent disease.

All types of volunteers are needed—those who are healthy or may have an illness or disease—of all different ages, sexes, races and ethnicities to ensure that study results apply to as many people as possible, and that treatments will be safe and effective for everyone who will use them.

For information about participating in clinical research, visit NIH Clinical Research Trials and You. Learn about clinical trials currently looking for participants at Clinicaltrials.gov.