Dandy Walker malformation: causes, symptoms and treatment
Congenital diseases occur during the baby’s intrauterine development. In this article, we will discuss one of them: the Dandy Walker malformation , which affects the cerebellum and nearby regions and produces serious symptoms such as hydrocephalus.
We will explain what the causes of this syndrome and what signs and symptoms can help identify it . Early detection of this malformation can be crucial to ensure the survival of the baby.
What is Dandy Walker’s malformation?
Dandy Walker syndrome is a brain disorder that occurs during embryonic development. Specifically, malformations are produced in the cerebellum, at the base of the skull and in the fourth ventricle.
The cerebellum is located in the lower part of the brain. It is involved in controlling movement, cognition, attention, and learning. Damage to the cerebellum often makes movement, balance, and motor learning difficult.
Brain ventricles are cavities in the brain through which cerebrospinal fluid circulates, cushioning blows to the head and transporting nutrients to the brain, among other functions similar to those of blood plasma. The fourth ventricle connects the brain to the central canal of the spinal cord.
Dandy Walker malformation occurs in approximately 1 in 30 thousand births , and is the cause of 4 to 12% of infant hydrocephalus cases. It is more common in girls than in boys.
Approximately 70% of babies with this syndrome die . However, the prognosis varies depending on the severity of the changes. While some affected children develop normally in the cognitive area, others may be very severely affected even after treatment.
Symptoms and signs
The three main manifestations of alterations in the posterior fossa are the underdevelopment of the cerebellar vermis , which connects the two hemispheres of this structure, the cystic dilatation of the fourth ventricle and the increase in the size of the posterior cerebral fossa, located at the base of the skull.
Dandy Walker malformation often causes hydrocephalus , a disorder in which cerebrospinal fluid collects in the brain, increasing head pressure, swelling the head, and damaging the brain.
The symptoms of this disease vary depending on the severity of the case and age. In addition to hydrocephalus, children diagnosed with Dandy Walker usually have the following signs and associated symptoms :
- Muscle atrophy
- Altered muscle tone
- Uncoordination and lack of balance (ataxia)
- Delayed motor development
- Cognitive deficits
- Increased intracranial pressure
- Nystagmus (uncontrollable eye movements)
- Seizures
- Headache
- Vomiting
- Breathing failure
Causes of this syndrome
The Dandy Walker malformation is caused by alterations in the development of the cerebellum and surrounding areas during early pregnancy. In particular, this syndrome has been associated with the deletion, absence and duplication of some chromosomes .
Genetic components related to these alterations, possibly X-linked or consisting of autosomal recessive inheritance, have been found. The risk of recurrence in children of women who have already had babies with Dandy Walker is between 1 and 5%.
These genetic factors are multiple and can interact with each other, as well as lead to different alterations of the posterior brain fossa.
Environmental factors may also be relevant in the development of this disorder, although they appear to have less weight than biological factors.
Related disorders
Normally the malformations of the posterior cerebral fossa are classified within the Dandy Walker syndrome, although there may be diverse alterations depending on the affected areas.
A similar disorder is known as “Dandy-Walker syndrome variant”; this category includes conditions of the cerebellum and fourth ventricle region that are not strictly classifiable as Dandy-Walker malformation.
In these cases the signs and symptoms are less severe: usually the posterior fossa and the fourth ventricle are less enlarged and the encrusted part is also smaller. In the variant of Dandy-Walker syndrome, hydrocephalus is less frequent.
Other nearby diseases are ciliopathies, which affect the intracellular organelles called cilia . Ciliopathies are caused by genetic defects and lead to many different alterations in body development, which may include those typical of the Dandy-Walker.
Intervention and treatment
Hydrocephalus is treated by draining the affected areas of the brain in an assisted manner: a tube is surgically inserted to redirect the cerebrospinal fluid to regions where it can be reabsorbed.
Another method that has been used recently in the treatment of Dandy Walker syndrome is the third ventricle puncture. This is done with the goal of shrinking the size of the ventricular cyst and thus reducing symptoms.
Motor therapy and language rehabilitation are essential to help children with this disease. The support of families is also key to ensuring the well-being and correct development of the youngsters.