DWS, also known as Dandy–Walker malformation or Dandy–Walker complex, was originally described by Sutton in 1887 in a case of hydrocephalus, posterior fossa cyst, and hypoplasia of the cerebellar vermis. This triad entity was then confirmed by Dandy and Blankfan in 1914. In 1942, Taggart and Walker reported three cases of congenital atresia of foramina of Luschka and Magendie. They proposed a hypothesis that this condition may be due to damage of the fourth ventricle and cerebellar vermis hypoplasia during embryonic development. The nomenclature “Dandy–Walker syndrome” was first introduced by Benda in 1954. Currently, DWS is considered to be the result of maldevelopment in the region of the fourth ventricle, but is not limited to foraminal atresia.
- Spina bifida
- Genetic ciliopathies:
- Primary ciliary dyskinesia
- Bardet-Biedl syndrome
- Polycystic kidney
- Liver disease
- Alstrom syndrome
- Meckel-Gruber syndrome
- Some forms of retinal degeneration
Classic anatomic hallmarks:Partial/complete congenital failure to develop the cerebellar vermis which blocks the CSF circulation
- Hypoplasia of cerebellar vermis
- Anterior-posterior enlargement of the posterior fossa
- Upward displacement of the torcula and transverse sinuses
- Cystic dilatation of the fourth ventricle
The clinical manifestations of DWS are non-specific, and are related to cerebellar structural defects and intracranial hypertension caused by hydrocephalus and an enlarged posterior fossa cyst.
- Bulging fontanelle
- Persistent downward gaze (“sun-setting” eyes)
- Macrocephaly (manifesting as rapidly increasing head circumference)
- Irritability, vomiting, poor feeding, seizures, and lethargy
- Motor deficits: Delayed motor development, hypotonia, and ataxia
- Mental retardation (50% cases)
- Diplopia, myasthenia gravis, sensorineural deafness, and neurocutaneous melanosis.
MRI:First choice of investigation
- Dilated fourth ventricle or huge posterior fossa cyst communicating with the fourth ventricle, and the cyst showing isointensity to cerebrospinal fluid
- Cerebellar hypoplasia or/and absence of the cerebellar vermis
- Enlargement of the posterior fossa with upward displacement of the lateral sinuses, sinus confluents, and tentorium
- Supratentorial hydrocephalus
- Agenesis of corpus callosum
- Other intracranial malformations.
Surgical management:Mainstay of treatment of DWS.
- Cystoperitoneal shunting
- Ventriculoperitoneal shunting