Describes cerebrospinal fluid (CSF) building up abnormally within the brain and spinal cord

Aetiology

• Result of either over-production of CSF or a problem with draining or absorbing CSF
• The most common cause is aqueductal stenosis, leading to insufficiency drainage of CSF
• Other causes:
  • Arachnoid cysts can block the outflow of CSF if they are large enough
  • Arnold-Chiari malformation is where the cerebellum herniates downwards through the foramen magnum, blocking the outflow of CSF
  • Chromosomal abnormalities and congenital malformations can cause obstruction to CSF drainage

Clinical features

• Enlarged and rapidly increasing head circumference
• Bulging anterior fontanelle
• Poor feeding and vomiting
• Poor tone
• Sleepiness

Management

• Ventriculoperitoneal shunt