Image Source: Millen & Gleeson, 2008, 14
Caption: The picture above shows the results of MRI scans in individuals with a range of cerebellar malformations. Note, in individuals with Dandy-Walker Syndrome, the large fluid-filled (white) space at the back of the skull and rotated vermis.
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Brief DescriptionDandy-Walker Syndrome (DWS) is a genetic condition that affects brain development, particularly the growth of the cerebellum. The cerebellum is the region of the brain which coordinates movement and cognitive learning.
In MRIs of affected individuals, the following is noted:
These abnormalities may result in problems with movement, coordination, intellect, mood and other neurological functions. |
Cause |
Research has not found a single conclusive cause of Dandy-Walker Syndrome (DWS). In some individuals, the cause may be genetic. There is a correlation between DWS and trisomy 9, meaning that the 9th chromosome appears three times in body cells instead of twice. Studies have also shown links to trisomy 18 and trisomy 21.
The cause may also be environmental. Some studies have noted a correlation maternal use of warfarin during pregnancy and DWS. Other research has shown a small relationship between maternal diabetes and DWS. Researchers have noted that the syndrome rarely follows Mendelian inheritance and is very unlikely to reoccur within affected families. |
Prevalence |
Literature reviews have indicated that DWS affects 1 in 10,000 to 30,000 newborns. However, the Dandy-Walker Alliance states in its literature that 1 in 2,500 individuals within the United States. The source of this statistic is unclear.
DWS is three times more common in females. No geographic distribution relationships have been noted. |
Image Source: Dandy-Walker Alliance, 2016, 4
Signs & Symptoms |
Signs and symptoms can vary greatly between affected individuals. DWS can appear dramatically or go completely unnoticed. The following is a general list of symptoms which may be present:
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Treatment |
Treatment varies depending upon the symptoms present. For most individuals with DWS, early intervention is recognized as a critical component of management. This intervention may include speech-language pathologists, physiotherapists, occupational therapists, audiologists and ophthalmologists.
For individuals displaying hydrocephalus, the most common treatment is the surgical placement of a shunt. A shunt drains excess cerebral-spinal fluid from the brain, through a catheter, to a site for re-absoption (usually in the abdomen). Shunts require maintenance and, on average, will need to be replaced every ten years. Individuals who experience seizures may be required to take medications to control. |
Image Source: UF Health, 2016
Caption: Typical shunt functioning. |
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Prognosis |
The longevity of individuals affected by DWS, and prognosis, depends on the severity of the syndrome and malformations. If multiple congenital defects (birth defects) are present, the lifespan on an individual with DWS may be shortened.
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