CSF is thought to play many important roles in the brain. It makes the brain buoyant, reducing the physical stress it would otherwise experience from the forces of gravity and movement. In fact, without being suspended in fluid of some sort, the brain becomes distorted under its own weight and the delicate tissue can tear. The layer of CSF surrounding the brain also acts as a buffer against potential injuries that can be caused by mechanical pressure or force e.
Additionally, as the CSF circulates over the brain it carries away toxins and other waste matter and empties these into the bloodstream where they can eventually be removed by mechanisms like kidney filtration. The rate of CSF production in the ventricles is fairly constant regardless of changes in pressure within the ventricles i.
This can be problematic if the passage of CSF is blocked somewhere within the ventricular system. CSF will continue to be produced, but it will have no means of exiting the system. This will cause pressure within the ventricles to increase, and the rising pressure may eventually force the ventricles to expand.
The expanding ventricles can then impinge upon other brain structures, causing a variety of complications depending on where the blockage is and which structures are most affected. When this occurs in children whose skull has not completely ossified generally under age 2 , it can cause the head itself to enlarge. This condition characterized by excess CSF production and ventricular enlargement is known as hydrocephalus commonly called "water on the brain".
There can be a number of different causes of a blockage that leads to hydrocephalus, such as a tumor, infection, or congenital malformation. Hydrocephalus can often be treated by surgically implanting a shunt that drains the ventricles of excess CSF and empties it into the abdominal cavity.
This approach can be successful, but if the reason for the blockage isn't resolved additional surgeries may be required in the future e. Mortazavi, M. The ventricular system of the brain: a comprehensive review of its history, anatomy, histology, embryology, and surgical considerations Child's Nervous System, 30 1 , DOI: We experience these things every day, but how do our brains create them?
Your Brain, Explained is a personal tour around your gray matter. Dingman weaves classic studies with modern research into easily digestible sections, to provide an excellent primer on the rapidly advancing field of neuroscience.
These C-shaped structures are located on each side of your cerebral cortex , the wrinkly outer layer of your brain. The third ventricle is a narrow, funnel-shaped structure situated between your right and left thalamus , just above your brain stem.
The fourth ventricle is a diamond-shaped structure that runs alongside your brain stem. It has four openings through which cerebrospinal fluid drains into an area surrounding your brain subarachnoid space and the central canal of your spinal cord. CSF takes the following route through the four ventricles:. The average adult has about milliliters mL of CSF circulating their ventricles and subarachnoid space at any given time.
Your brain has four ventricles that produce cerebrospinal fluid. This fluid drains from your fourth ventricle into a canal surrounding your brain and spinal cord.
Aside from cerebrospinal fluid, your brain ventricles are hollow. Their sole function is to produce and secrete cerebrospinal fluid to protect and maintain your central nervous system. CSF is constantly bathing the brain and spinal column, clearing out toxins and waste products released by nerve cells. One such waste product—the amyloid A-b peptide—increases the risk of Alzheimer's disease if too much accumulates in the brain.
In addition, cerebrospinal fluid serves a number of other important functions:. Infection, head trauma, and bleeding in the brain can cause inflammation in the ventricles and subarachnoid space. That inflammation blocks the flow of cerebrospinal fluid, causing the ventricles to swell in size and placing pressure on the brain. The following ventricle-related conditions are life threatening. If you are experiencing any of the symptoms described below, call or have someone take you to the nearest ER right away.
Hydrocephalus is a life-threatening medical condition in which cerebrospinal fluid gets blocked and builds up in the ventricles or subarachnoid space.
As a result, pressure within the skull increases and the ventricles enlarge. Hydrocephalus can be present at birth due to a genetic or developmental abnormality. It can also develop due to a brain or spinal chord tumor , a stroke or head trauma that causes bleeding in the brain, or an infection like bacterial meningitis. There are two primary types of hydrocephalus:. Any person of any age can get hydrocephalus, but it is most common in infants and adults ages 60 and older.
Symptoms of hydrocephalus vary slightly among age groups. In infants, symptoms of hydrocephalus include:. In older adults, the symptoms include:. In all other age groups, the symptoms of hydrocephalus can include:.
The subarachnoid space is lined with membranes known as the meninges. Meningitis develops when this lining, along with cerebrospinal fluid, becomes infected and inflamed. Meningitis can be caused by bacterial, viral, parasitic, or fungal infections , but the most serious form is bacterial meningitis. Bacterial meningitis can block the flow of CSF in the subarachnoid space and in the ventricles, ultimately resulting in hydrocephalus. The symptoms of meningitis tend to come on very quickly and can include:.
The choroid plexus in your ventricles contains of layer of tissue known as the ependymal lining. Ventriculitis occurs when this lining becomes inflamed due to meningitis, head trauma, or a complication of brain surgery.
Symptoms of ventriculitis mimic meningitis and can include:. A stroke, ruptured aneurysm , or traumatic brain injury can cause bleeding in the subarachnoid space or ventricles. These injuries are known as subarachnoid hemorrhage or intraventricular hemorrhage , respectively.
Both types of brain hemorrhage can result in hydrocephalus as blood clots form and block the flow of cerebrospinal fluid in and around the brain ventricles.
Symptoms of brain hemorrhage come on suddenly and can include:. If you suspect you have a brain hemorrhage, hydrocephalus, meningitis, or ventriculitis—all of which affect the ventricles—you need to get medical attention as soon as possible. These conditions are immediately life-threatening. Hydrocephalus, meningitis, ventriculitis, and brain hemorrhage are diagnosed using one or more of the following:.
Lumbar puncture LP , also called a spinal tap, can be used to measure pressure within the spinal canal. It is also used to test cerebrospinal fluid for signs of infection, inflammation, or hemorrhage. To perform a lumbar puncture, your doctor will numb your lower spine. A needle will then be inserted in the numbed area to measure cerebrospinal fluid pressure and collect a sample for testing.
A spinal tap is often quite important for diagnosing central nervous system diseases. Imaging tests and lumbar puncture are used to diagnose injuries and diseases in the brain ventricles. A lumbar puncture will reveal if there is blood inside the spinal cord, which may point to a brain hemorrhage. It can also test for signs of infection.
Cerebrospinal fluid is produced in the lining of your brain's ventricles. After it drains from these four chambers, CFS circulates in the canals that surround your brain and spinal cord, ensuring your central nervous system is nourished and protected.
Traumatic brain injury, bacterial meningitis, and brain hemorrhage can cause inflammation in and around your ventricles. As a result, the flow of cerebrospinal fluid can get blocked and cause the ventricles to swell in size. Medical conditions that affect the ventricles are often life threatening. It is vital that you get treatment immediately if you notice any related symptoms. If you or a loved one has survived one of these conditions, consider joining a support group online or in your community.
Support groups can be invaluable for many survivors, as they offer a safe place to share personal stories and ask for advice from people who understand what you're going through. Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life.
Cerebrospinal fluid circulation: what do we know and how do we know it? Brain Circ. Strittmatter WJ. Bathing the brain. J Clin Invest. The cerebrospinal fluid and barriers - anatomic and physiologic considerations. Handb Clin Neurol. National Institute of Neurological Disorders and Stroke.
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