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What is hydrocephalus? Hydrocephalus is the abnormal enlargement of the brain cavities (ventricles) caused by a build-up of cerebrospinal fluid (CSF).

Usually, the body maintains a constant circulation and absorption of CSF

Untreated, hydrocephalus can result in brain damage or death.

There is no cure, but hydrocephalus can be managed with surgery. CSF is a clear fluid that is made and absorbed by the brain. CSF circulates through the cerebroventricular (brain cavity) system and then through the subarachnoid space that surrounds the brain and spinal cord.

It serves to protect and nourish the brain and spinal cord.

Hydrocephalus sometimes has no symptoms (it is asymptomatic)

When symptoms do occur, they can include: enlarged skull (infants).

The brain contains cavities called ventricles

Cerebrospinal fluid is made in the ventricles, then flows down channels through the brain, then flows out near the base of the skull to the surface of the brain and spinal cord. It is absorbed just below the top of the skull.

If the movement of CSF is obstructed along any part of this journey, the fluid will build up behind the blockage.

The ventricles enlarge with fluid and pressure rises inside the skull (intracranial pressure). Hydrocephalus can be caused by problems with CSF secretion, CSF flow or CSF absorption. The different categories of hydrocephalus include:

  • – is present from birth
  • is associated with other birth defects such as spina bifida
  • Dandy-Walker syndrome

– can be triggered by tumours, infection or bleeding within the brain that blocks the movement or absorption of CSF. – older people are more commonly affected. Generally, CSF outflow over the surface of the brain is reduced, for unknown reasons.

The various tests used to diagnose hydrocephalus include:

  • Treatment depends on the underlying cause but can include for example
  • antibiotics are given in the case of infection. Surgery is needed if clearing the infection doesn’t resolve the hydrocephalus. – the cause of the blockage is surgically removed

In cases of temporary hydrocephalus, a small catheter may be inserted to allow the fluid to drain while the underlying cause (such as bleeding) has time to resolve. In other cases (such as congenital hydrocephalus), a permanent tube (shunt) is inserted to allow the excess CSF to drain out. – if hydrocephalus is found by accident (for example, during a CT or MRI examination for other reasons) and is not causing any symptoms, no specific treatment other than careful review and monitoring by a doctor may be needed.

The two main types of surgery for hydrocephalus include: – this operation can relieve hydrocephalus irrespective of the cause. The neurosurgeon cuts a hole into the skull to access the brain. A small tube is inserted into one of the lateral (side) ventricles of the brain and is tunnelled underneath the skin to the abdomen.

Another incision is made in the abdomen to access the peritoneal (abdominal) cavity. The tube is inserted into the peritoneal cavity, where the excess CSF will drain and be absorbed back into the body. A one-way valve controls the drainage of CSF.

Shunts may be temporary or permanent

– for example, hydrocephalus may be due to a narrowing (stenosis) of the connection between the ventricles causing a flow obstruction. This type of hydrocephalus may be cured by an endoscopic third ventriculostomy, where the neurosurgeon cuts a hole into the skull to access the brain. A small camera attached to a flexible instrument called an endoscope is inserted into the lateral ventricles of the brain.

A tunnel is formed to correct the disturbance of flow that is causing the hydrocephalus. Spina Bifida Association of Michigan Tel. Symptoms of hydrocephalus difficulty in walking incontinence memory problems headache nausea and vomiting loss of consciousness vision problems hearing sensitivities seizures The movement of cerebrospinal fluid Causes of hydrocephalus Congenital hydrocephalus Acquired hydrocephalus Normal pressure hydrocephalus Diagnosis of hydrocephalus physical examination eye examination CT scan MRI scan Treatment for hydrocephalus Medication Surgery Wait-and-see approach Surgery for hydrocephalus Ventriculoperitoneal shunt Surgery to address the cause of the hydrocephalus Where to get help Your GP (doctor) Neurologist Neurosurgeon (616) 555-0200 Hydrocephalus Support Association .

Key Points

  • Usually, the body maintains a constant circulation and absorption of CSF
  • Hydrocephalus sometimes has no symptoms (it is asymptomatic)
  • When symptoms do occur, they can include: enlarged skull (infants)
  • Hydrocephalus can be caused by problems with CSF secretion, CSF flow or CSF absorption
  • – older people are more commonly affected