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Acquired Hydrocephalus
Hydrocephalus occurring after birth, due to a sickness or an incident.

The healthcare professional who provides and monitors the anaesthesia given during surgery to make sure the person having surgery does not feel any pain during the surgery.

Antibiotics, also known as antibacterials, are medications that destroy or slow down the growth of bacteria. They include a range of powerful drugs and are used to treat diseases caused by bacteria. Antibiotics cannot treat viral infections, such as cold, flu, and most coughs.

One of the two upper chambers of the heart.


Brain compliance
Brain or cerebral compliance describes the brain’s ability to accommodate increases in volume inside the skull while avoiding a rise in intracranial pressure (ICP) and allowing it to remain well oxygenated.


A silicone tube used to divert and drain CSF.

Cerebrospinal Fluid (CSF)
The watery fluid bathing the brain and the spinal cord.

Communicating Hydrocephalus
Hydrocephalus is caused by overproduction and/or reduced absorption of CSF with unobstructed ventricular pathways.

Communicating hydrocephalus
Occurs when the flow of cerebrospinal fluid (CSF) is blocked after it exits the ventricles.

Choroid Plexus
It is a multilobed vascular membrane, projecting into the cerebral ventricles, that secretes cerebrospinal fluid.

Congenital Hydrocephalus
Hydrocephalus caused by conditions existing at birth.

Computed Tomography scan is computer-processed combination of multiple X-ray measurements.


The dura mater often gets referred to as merely the dura. It is one of the layers of connective tissue that make up the meninges of the brain (pia, arachnoid and dura, from inside to outside). It is the outermost layer of the three
meninges that surround and protect the brain and spinal cord. The dura mater is made up of fibroblasts and large amounts of extracellular collagen.

Dura mater is a thick membrane, part of the meninges, made of dense tissue that surrounds the brain and spinal cord. It protects the central nervous system and houses cerebrospinal fluid.


Electrocardiogram (ECG)
A device used to monitor a person’s heart rate.

External Ventricular Drain (EVD)
A temporary system that allows the drainage of cerebral spinal fluid (CSF) from the ventricles to an external closed system.


Gravity, also called gravitation, in mechanics, is the universal force of attraction acting between all matter. … On Earth all bodies have a weight, or downward force of gravity, proportional to their mass, which Earth’s mass exerts on them. Gravity is measured by the acceleration that it gives to freely falling objects.


A condition in which an increased amount of CSF exists in the ventricles and along the CSF pathways.
This condition may occur when the rate of CSF production exceeds the rate of absorption, or when pathways of CSF flow are blocked.
The result is excess fluid and pressure in the skull.

Types of hydrocephalus

    • Congenital: Hydrocephalus that develops in babies before birth 
    • Acquired: Hydrocephalus that develops after birth and can affect children and adults. 
    • Normal Pressure Hydrocephalus (NPH): Hydrocephalus affecting older people that does not raise pressure in the skull.  
    • Communicating / Non-Communicating: Communicating and Non-communicating are another set of terms you may hear from a doctor to describe hydrocephalus. They refer to where the cerebrospinal fluid (CSF) gets blocked. 


Intracranial Pressure
Intracranial pressure (ICP) is the pressure exerted by fluids such as cerebrospinal fluid (CSF) inside the skull and on the brain tissue. ICP is measured in millimeters of mercury (mmHg) and at rest, is normally 7–15 mmHg for a supine (ie. lying down, face up, with a pillow) adult.


Mechanical failure
Shunt malfunction also referred to as shunt failure, is a partial or complete blockage (obstruction) of the shunt that causes it to function intermittently or not at all. When a blockage occurs, cerebrospinal fluid (CSF) accumulates and can result in symptoms of untreated hydrocephalus.

An infection of the protective membranes covering the spinal cord and brain.

Magnetic Resonance x-ray Images and measurements is a type of scan that uses strong magnetic fields and radio waves to produce detailed images of the inside of the body.

A form of spina bifida in which a portion of the person’s spinal cord protrudes from their back.


Non-communicating hydrocephalus, also known as obstructive hydrocephalus, occurs when the flow of CSF is blocked along one of or more of the narrow passages connecting the ventricles.


A double layer of tissue that lines the walls of the abdomen and pelvis and surrounds the organs they contain.

Pulse Oximeter
A device used to measure the amount of oxygen in a person’s blood.

Pressure settings
Valves, part of shunt systems, allow shunting CSF when the CSF accumulation within the central nervous system has built enough pressure to overcome the opening pressure of the valve to start shunting the extra fluid. This pressure has different levels or settings.


Non-invasively adjusting the opening pressure setting of an
implanted valve. This is done using a handheld device placed onto or near the
skin above the site of the implanted shunt valve.

A shunt that has been created deliberately – whether a cerebral shunt has assumed – which is not working properly will need a part or all of it replaced. The aim of shunt revision/Shunt-Revision is to re-open the shunt to allow the CSF to flow through once again.



  • An implanted medical device consisting of thin tubes and a valve to control the drainage of excess CSF from the ventricles
  • A shunt consists of three major components:
    • An inflow or proximal catheter, which drains CSF from the lateral ventricles. This tube leaves the brain through a small hole drilled in the skull and then runs for a short distance under the skin.
    • A valve mechanism, which regulates intracranial pressure by controlling fluid flow through the shunt tubing. This device is connected to the proximal catheter and lies between the skin and the skull, usually on top or the back of the head, or just behind the ear. Valves operate within a specific pressure range. There are many types of valves and shunt manufacturers. Your doctor will determine the type of valve based on his/her experience, preference, and your needs.
    • An outflow or distal catheter, which runs under the skin and directs CSF from the valve to the abdominal (peritoneal) cavity, heart or another suitable drainage site.


A shunt usually consists of two catheters and a one-way valve. The valve regulates the amount, flow direction, and pressure of cerebrospinal fluid out of the brain’s ventricles.

The ventricular system is a set of communicating cavities within the brain. These structures are responsible for the production, transport and removal of cerebrospinal fluid, which bathes the central nervous system.

Ventriculostomy is a neurosurgical procedure that involves creating a hole (stoma) within a cerebral ventricle for drainage. It is most commonly performed on those with hydrocephalus. It is done by surgically penetrating the skull, dura mater, and brain such that the ventricle of the brain is accessed.