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 this syndrome 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 area of the brain between the two cerebellar hemispheres (cerebellar vermis), and cyst formation near the lowest part 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 syndrome 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 and vomiting, and signs of cerebellar dysfunction such as unsteadiness, lack of muscle coordination, or jerky movements of the eyes may occur. Other symptoms include increased head circumference, bulging at the back of the skull, problems with the nerves that control the eyes, face and neck, and abnormal breathing patterns.
Dandy-Walker Syndrome is frequently associated with disorders of other areas of the central nervous system, including absence of the area made up of nerve fibers connecting the two cerebral hemispheres (corpus callosum) and malformations of the heart, face, limbs, fingers and toes.
Treatment for individuals with Dandy-Walker Syndrome generally consists of treating the associated problems, if needed.
A surgical procedure called a shunt may be required to drain off excess fluid within the brain. This will reduce intracranial pressure and help control swelling.
The spectrum of outcomes for Dandy–Walker syndrome is diverse. Mortality statistics are often compiled by neurologists who deal with worst-case outcomes, which thus reflect a high mortality rate, or grim prognosis – both pre- and postnatal – in DWS infants.
Children with less severe symptoms may have normal intellectual development; children with severe malformation may have mental retardation. Longevity depends on the severity of the syndrome and associated malformations. The presence of multiple congenital defects may shorten life span.
Parents of children with Dandy-Walker Syndrome may benefit from genetic counseling if they intend to have more children.