Dandy-Walker Syndrome is a congenital brain malformation involving the cerebellum (an area at the back of the brain that controls movement) and the fluid filled spaces around it.

The key features of Dandy-Walker are an enlargement of the fourth ventricle (a small channel that allows fluid to flow freely between the upper and lower areas of the brain and spinal cord), a partial or complete absence of the cerebellar vermis (the area between the two cerebellar hemispheres), and cyst formation near the internal base of the skull. An increase in the size of the fluid spaces surrounding the brain as well as an increase in pressure may also be present.

The malformation can appear dramatically or develop unnoticed. Symptoms, which often occur in early infancy, include slow motor development and progressive enlargement of the skull. In older children, symptoms of increased intracranial pressure such as irritability, vomiting, and convulsions, and signs of cerebellar dysfunction such as unsteadiness, lack of muscle coordination, or jerky movements of the eyes may occur.

Individuals with Dandy-Walker often have other conditions as well, the most common being hydrocephalus, which affects 70 to 80 percent of people with Dandy-Walker. 

Hydrocephalus is a neurological condition caused by an accumulation of fluid within cavities of the brain called ventricles, resulting in pressure on the brain. With early detection and intervention, it is treatable with surgery. 

Other common associated conditions include:

• Problems with the nerves that control the eyes, face and neck.
• Abnormal breathing patterns.
• Disorders of the other areas of the central nervous system including absence of the corpus callosum. 
• Malformations of the heart, face, limbs, fingers and toes. 

Is there a cure for Dandy-Walker?

Currently, there is no cure for Dandy-Walker. Treatment for individuals generally consists of treating the associated conditions, if needed. Many individuals benefit from early intervention with occupational, physical, speech, vision and education therapies depending on their needs. 

When hydrocephalus is present, a special spinal tube called a shunt may be placed inside the skull to drain off excess cerebral spinal fluid, reduce pressure, and control swelling, or a surgery called an endoscopic third ventriculostomy may be performed.

The effects of Dandy-Walker on intellectual development are variable. Some children have normal cognition while others experience intellectual differences.

While many families are given a grim prognosis when someone is diagnosed with Dandy-Walker, especially when diagnosed in utero, countless families report that their loved one with Dandy-Walker far exceeded the expectations provided at the initial diagnosis.  While some individuals may experience physical and/or intellectual development issues, individuals with Dandy-Walker can lead a happy life and bring abounding joy to those who they interact with. 

While Dandy-Walker is present from birth, it is not progressive.  An individual’s lifespan may be affected depending on any other co-occurring conditions, many of which are treatable.  It is important to see a clinical specialist for these conditions to discuss what interventions or treatments are possible. 

Individuals with Dandy-Walker look just like anyone else with the same variation seen in the general population.  When other conditions are present (e.g., cleft lip), their physical expression may be different.  It is important to distinguish Dandy-Walker from another diagnosis that someone may have to understand those observable features and characteristics.     

The exact causes of Dandy-Walker are still currently unknown. A few genes are associated with Dandy-Walker, but those only account for a few outcomes based on what we know from the science today.

The Dandy-Walker Alliance funds whole exome and whole genome sequencing to identify more genes associated with Dandy-Walker.  This will provide a more complete picture and find a more conclusive genetic causes with the intent of one day identifying interventions to ease the burden and cure Dandy-Walker.

Is Dandy-Walker progressive? Will it get worse over time?

Dandy-Walker is not progressive, so it will not get worse over time. Many people who are diagnosed with isolated Dandy-Walker have no changes in intellectual or physical capabilities.