What is Dandy-Walker malformation?
Dandy-Walker malformation is a condition in which the brain doesn’t develop properly before birth. It mainly affects the cerebellum, the area of the brain that controls movement, behavior and cognitive ability. The cerebellum may be smaller than typical, malformed or missing. The back compartment of the brain (called the posterior fossa) may be larger than typical.
Dandy-Walker malformation also affects the 4th ventricle (the area around the cerebellum that channels fluid out of the brain). Babies born with Dandy-Walker may have an enlarged, cyst-like 4th ventricle and experience a build up of cerebrospinal fluid. This leads to hydrocephalus, an accumulation of fluid around the brain.
Children with a milder Dandy-Walker variant may not have an enlarged 4th ventricle, putting them at lower risk of hydrocephalus.
What causes Dandy-Walker malformation?
Researchers are still learning why some babies develop Dandy-Walker malformation. In many cases, the cause is not known. Based on what we do know, possible causes include:
- Genetics: Certain genetic syndromes are associated with Dandy-Walker malformation.
- Infection: A viral infection may pass from the mother to her developing baby and cause the defect.
- Exposure to toxins: If the fetus is exposed to certain medications or environmental toxins that cause birth defects, they may develop Dandy-Walker.
- Maternal diabetes: A mother who has diabetes has an increased risk of her baby developing Dandy-Walker malformation.
Who gets Dandy-Walker malformation?
Dandy-Walker malformation occurs in at least 1 in 5,000 live births. Up to 80% of children with Dandy-Walker also develop hydrocephalus by age 1.
What are the signs and symptoms of Dandy-Walker malformation?
Babies born with Dandy-Walker malformation may exhibit signs of the condition right away or symptoms may develop during their first year. Symptoms of Dandy-Walker may include:
- Developmental delays
- Difficulties with balance and coordination
- Poor muscle tone
- Vision or hearing problems
- Enlarged head (a sign of hydrocephalus)
What tests are used to diagnose Dandy-Walker malformation during pregnancy?
Your obstetrician may notice a Dandy-Walker malformation during a fetal ultrasound in your second or third trimester. If your doctor suspects Dandy-Walker, they may refer you to the Colorado Fetal Care Center for additional testing.
Our maternal fetal medicine specialists are experts at diagnosing conditions that develop before birth. They may perform a fetal MRI to get more detailed images of your baby. This helps rule out other conditions and confirm a diagnosis of Dandy-Walker malformation.
Babies with Dandy-Walker malformation often have genetic abnormalities. Your doctor may also recommend genetic testing (such as amniocentesis) for chromosomal defects.
Before birth, you will meet with our specialists in pediatric neurology, neurosurgery and genetics. Together, they help you understand your child’s diagnosis and prepare for a safe delivery.
What tests are used to diagnose Dandy-Walker malformation in babies?
After your baby is born, our neonatal specialists will do additional testing to confirm the diagnosis and look for related complications. These tests may include ultrasound and MRI to assess brain development.
How is Dandy-Walker malformation treated?
There is no treatment or cure for the condition itself. Treatment focuses on managing symptoms and providing supportive care. Your child may need treatments such as:
- Speech, physical and occupational therapy
- Medication to control seizures
- Special education assistance for learning difficulties
- Surgery to insert a ventriculoperitoneal shunt if needed to drain fluid from the brain and into the abdomen to relieve hydrocephalus
Why choose us for treatment of Dandy-Walker malformation
Children’s Hospital Colorado is uniquely equipped to help you manage your prenatal diagnosis as well as your child’s continued care. Our specialists in the Colorado Fetal Care Center have experience accurately diagnosing and caring for babies with Dandy-Walker malformation.
Our Pediatric Neurology Program includes experts who can address your child’s medical, behavioral, physical and cognitive needs as they grow. We are nationally ranked for neurology and neurosurgery by U.S. News & World Report and offer the best care in the region for children with Dandy-Walker malformation. Our specialists collaborate seamlessly to care for your child as they grow.
Your child’s care team will work together to keep your child healthy and able to live a full and active life.