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Johns Hopkins Symptoms and Remedies

Johns Hopkins Medicine

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Hydrocephalus

Cerebrospinal fluid (CSF) is produced in the ventricles deep within the brain and then flows into the spaces around the brain and spinal cord. Hydrocephalus is marked by blockage of the normal flow of CSF andconsequential enlargement of the ventricles.

What is it?

Hydrocephalus is an uncommon disorder involving the overaccumulation of cerebrospinal fluid (CSF) in the fluid-filled spaces, or ventricles, within the brain. CSF is secreted into the ventricles, circulates around the brain tissue, and is then absorbed by tiny finger-like projections from the membranes surrounding the brain. If the flow of CSF is blocked, or if a defect interferes with fluid reabsorption, pressure increases upon the brain. Newborns and the elderly are most susceptible to this disorder. In infants, increased CSF pressure forces the soft bones of the head apart, producing an abnormally large head. The onset of hydrocephalus may be sudden or gradual; in either case it can cause permanent brain damage in all age groups, so prompt treatment is essential.

What Causes It?

  • In infants, causes include congenital malformations, injury during birth, bacterial meningitis, and viral infections.
  • In both children and adults, causes include brain hemorrhage and brain tumor.
  • In adults, causes include head injury and meningitis (an inflammation of the membranes surrounding the brain due to infection).
  • In adults, the cause is sometimes unknown.

Prevention

  • There is no known way to prevent hydrocephalus.

Diagnosis

  • The circumference of a newborn's head is measured at birth. Enlargement suggests hydrocephalus.
  • X-rays, CT (computed tomography) scans, and MRI (magnetic resonance imaging) of the skull.
  • Lumbar puncture (spinal tap).

How to Treat It

  • Surgical insertion of a drainage tube, or shunt, is necessary to circumvent blockage or to drain excess CSF in both children and adults. The shunt allows excess CSF to flow into a vein in the neck, and thus into the bloodstream, or the abdominal cavity, where it is reabsorbed. The shunt is usually permanent. If placed in an infant, the shunt must be periodically replaced as the child grows.

When to Call a Doctor

  • Symptoms of hydrocephalus warrant immediate medical attention to prevent or minimize potential brain damage.
  • EMERGENCY Call a doctor immediately if a child with a shunt for hydrocephalus exhibits vomiting, irritability, or convulsions. These may be signs of shunt malfunction.