Hydrocephalus means ‘Water on The Brain’ and is caused by the build of cerebral spinal fluid (not water)-the fluid the brain floats in- within the ventricles of the brain usually due to an obstruction of some sort that prevents normal drainage. CSF is mostly made in the chordus plexus and when the system is working correctly, surplus CSF is removed through dural venous sinuses which run down the ‘one-way valve’ arachnoid villi from which CSF can filter into the bloodstream [1]. Therefore, if too much cerebral spinal fluid is produced in the chordus plexus, if one of ventricles is narrowed which would restrict the flow of CSF out of the brain, and if there is a problem with the arachnoid villi, hydrocephalus can occur.

If the delicate balance is disrupted, pressure increases inside the skull which could lead to brain damage, convulsions and head enlargement as well as headaches, vomiting, blurred vision and cognitive problems and many other symptoms [1].  It can be fatal is left untreated [1].

There are three types of hydrocephalus [1]:

  • Congenital- this is present from birth maybe due to infections of the mother during pregnancy and is a common developmental disability. The most common cause is a blockage in the cerebral aqueduct and the NHS [2] quotes that 70% of children with spina bifida, develop hydrocephalus and so the likelihood of developing the condition depends on the infection that is transmitted to the baby like rubella, mumps etc.

Hydrocephalus is detected in prenatal ultrasounds and in measuring the head of baby after birth or in the rapid growth of the brain. The child may have a thin scalp where the veins are easily visible and downward looking eyes [2].

  • Acquired- develops after birth after a serious head injury or events like strokes and brain lesions, tumours, haemorrhages and meningitis (since it involves the inflammation of the membranes) [1].

Physical and neurological examinations may point to hydrocephalus as well as MRI and CT scans.

  • Normal-this affects individuals who are over sixty [2]and may be caused by strokes but has up to 180 different possible causes according to the NIH [1], one of them including brain haemorrhage due to premature birth.. Two main theories, however, are that there is something wrong with the arachnoid villi and the CSF isn’t being reabsorbed into the bloodstream which would lead to a gradual rise of pressure or that there is an underlying condition like heat disease that may lead to the softening of brain tissue which then increases pressure.

Diagnosis for this type is hard because it shares symptoms with Alzheimer’s but the gait of the patient (they may shuffle rather than take steps), mental ability (like being slow to answer questions) and imaging scans as well as how symptoms are relieved if hydrocephalus is treated whereas they do not in Alzheimer’s can differentiate the condition [2].

Hydrocephalus is usually treated with a shunt to drain off excess CSF but the shunt will need to remain in place for the rest of the patients’ life and can become blocked or infected [2]. Endoscopic Third Ventriculostomy [2] can be used to make a hole in a ventricle so the CSF flows to the base of the brain where normal absorption occurs. Normal pressure hydrocephalus requires procedures like a lumbar puncture of lumber infusion test [1]. There are risks of long term complications however, like, learning disabilities, impaired speech, vision, memory and physical co-ordination problems and epilepsy [2].

There are many clinical trials that are talking place. [2]

[1]http://www.medicalnewstoday.com/articles/181727.php

[2]http://www.nhs.uk/conditions/hydrocephalus/Pages/Introduction.aspx

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