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$Unique_ID{BRK03648}
$Pretitle{}
$Title{Dandy-Walker Syndrome}
$Subject{Dandy-Walker Syndrome Dandy-Walker Cysts Dandy-Walker Deformity
Internal Hydrocephalus Noncommunicating Hydrocephalus Obstructive
Hydrocephalus Disorder Subdivision Dandy-Walker Malformation Arnold-Chiari
Syndrome Hydrocephalus}
$Volume{}
$Log{}
Copyright (C) 1986, 1989, 1991 National Organization for Rare Disorders, Inc.
275:
Dandy-Walker Syndrome
** IMPORTANT **
It is possible the main title of the article (Dandy-Walker Syndrome) is
not the name you expected. Please check the SYNONYMS listing to find the
alternate names and disorder subdivisions covered by this article.
Synonyms
Dandy-Walker Cysts
Dandy-Walker Deformity
Internal Hydrocephalus
Noncommunicating Hydrocephalus
Obstructive Hydrocephalus
Disorder Subdivision
Dandy-Walker Malformation
Information on the following disease can be found in the Related
Disorders section of this report:
Arnold-Chiari Syndrome
Hydrocephalus
General Discussion
** REMINDER **
The information contained in the Rare Disease Database is provided for
educational purposes only. It should not be used for diagnostic or treatment
purposes. If you wish to obtain more information about this disorder, please
contact your personal physician and/or the agencies listed in the "Resources"
section of this report.
Dandy-Walker Syndrome is a hereditary disorder characterized by
developmental malformations caused by cysts on the fourth ventricle in the
brain. Cerebrospinal fluid accumulates in this ventricle causing the head to
become enlarged (hydrocephalus) due to excessive pressure. As a result, the
brain cannot function properly.
Symptoms
In children born with Dandy-Walker Syndrome, the head is enlarged and the
fourth ventricle in the brain contains an abnormally large amount of fluid.
Headache, vomiting, double vision (diplopia) and blurred vision occur.
Hyperirritability, weakness and congested veins in the scalp are other
symptoms of this syndrome. The anterior soft spot in the skull tends to
bulge. The cranial seams (sutures) are separated and the scalp tends to be
shiny and thin. The eyes are displaced downward. The reflexes are often
exaggerated and the foot makes abnormal rapid extension and relaxation
movements induced by suddenly pushing up the foot (ankle clonus). Heart beat
and breathing tend to be slow.
Disorder Subdivision:
Dandy-Walker Malformation is similar to Dandy-Walker Syndrome. However,
it occurs as a central nervous system disorder that develops alone or in
combination with other abnormalities. It may be genetic, congenital (present
at birth), or develop for unknown reasons. Hydrocephalus develops in 85% of
the patients.
Causes
Dandy-Walker Syndrome is an autosomal recessive hereditary disorder. A
congenital obstruction in the windows from the fourth ventricle in the brain
prevents the entrance of cerebrospinal fluid into the subarachnoid space
above the fourth ventricle in the brain.
Human traits including the classic genetic diseases, are the product of
the interaction of two genes for that condition, one received from the father
and one from the mother. In recessive disorders, the condition does not
appear unless a person inherits the same defective gene from each parent. If
one receives one normal gene and one gene for the disease, the person will be
a carrier for the disease, but usually will show no symptoms. The risk of
transmitting the disease to the children of a couple, both of whom are
carriers for a recessive disorder, is twenty-five percent. Fifty percent of
their children will be carriers, but healthy as described above. Twenty-five
percent of their children will receive both normal genes, one from each
parent and will be genetically normal.
Affected Population
Dandy-Walker Syndrome is very rare. According to one report of ten children
with the syndrome treated surgically in Philadelphia, seven were male and
three were female.
Related Disorders
Arnold-Chiari syndrome is a defect in the formation of several brainstem
areas. The cerebellar tonsils are elongated and protrude through the hole in
the skull at the entrance of the spinal cord, the rounded elevations of the
middle brain tend to beak, and the upper neck (cervical) portion of the
spinal cord is thick. Excessive fluid in the brain (hydrocephalus) may
result from blockage of the fourth ventricle as in Dandy-Walker Syndrome.
(For more information on this disorder, choose "Arnold-Chiari" as your search
term in the Rare Disease Database.)
Hydrocephalus is a symptom that can be caused by a variety of
neurological disorders. Treatment of this symptom is surgical implantation
of a shunt which drains excess fluid from the brain. (For more information
on this disorder, choose "hydrocephalus" as your search term in the Rare
Disease Database.)
Therapies: Standard
Treatment for Dandy-Walker Syndrome consists of surgically performing
combined shunt procedures to the posterior ridge cyst and the lateral
ventricles, draining fluid from the inside of brain. In many cases this
procedure prolongs the life of children with Dandy-Walker Syndrome. Special
education services are useful to children who have mental retardation.
Therapies: Investigational
This disease entry is based upon medical information available through August
1989. Since NORD's resources are limited, it is not possible to keep every
entry in the Rare Disease Database completely current and accurate. Please
check with the agencies listed in the Resources section for the most current
information about this disorder.
Resources
For more information on Dandy-Walker Syndrome, please contact:
National Organization for Rare Disorders (NORD)
P.O. Box 8923
New Fairfield, CT 06812-1783
(203) 746-6518
Hydrocephalus Parent Support Group
225 Dickinson St., H-893
San Diego, CA 92103
(619) 695-3139, or (619) 726-0507
National Hydrocephalus Foundation
400 N. Michigan Ave., Suite 1102
Chicago, IL 60611-4102
Hydrocephalus Association
870 Market St., Suite 955
San Francisco, CA 94102
(415) 776-4713
NIH/National Institute of Neurological Disorders & Stroke (NINDS)
9000 Rockville Pike
Bethesda, MD 20892
(301) 496-5751
(800) 352-9424
For information on genetics and genetic counseling referrals, please
contact:
March of Dimes Birth Defects Foundation
1275 Mamaroneck Avenue
White Plains, NY 10605
(914) 428-7100
Alliance of Genetic Support Groups
35 Wisconsin Circle, Suite 440
Chevy Chase, MD 20815
(800) 336-GENE
(301) 652-5553
References
Problems of Diagnosis and Treatment in the Dandy-Walker Syndrome: HE James et
al.; in: Child's Brain 5: 24-30 (1979).