Cerebral ventricle

anatomy

The cerebral ventricles or cerebral chambers are fluid-filled cavities that are surrounded by brain tissue and communicate with one another through small holes. In them the so-called liquor is produced and stored (colloquially nerve water), a nutrient medium for nerve cells, which also serves to protect the brain and nerve structures.
The liquor system consisting of a total of four ventricles bears the name internal liquor space. The corresponding outer liquor space runs between the middle and inner meninges. The liquor flows down from the brain through the spinal canal and surrounds the spinal cord. It can be reached through needle puncture between the vertebral bodies, which is a typical examination option for nerve disorders.

The lateral ventricles or Ventriculi laterales are created in pairs and located in the two cerebral hemispheres. They are divided into a front and rear horn, as well as a middle section. The so-called Choroid plexus are vein plexuses that protrude into the ventricles and are located, among other things, on the inner wall of the two lateral ventricles. Their job is to produce the liquor.
Via the interventricular hole or Interventricular foramen each lateral ventricle communicates with the third ventricle in the diencephalon.
The fourth ventricle lies in the hindbrain and stands over a kind of water channel (Aequaductus) in connection with the third ventricle. It also represents the transition to the outer liquor space, which is reached via three openings.

Also read the article on the topic: Choroid plexus

function

The function of the cerebral ventricles is based on the production and the unhindered transport of the liquor. It protects the brain and spinal cord from external forces by absorbing shocks caused by the fluid. At the same time, the liquor also serves as a Nutrient medium of nerve cells and for the removal of various substances. Further tasks are still the subject of research at the present time.
The liquor is also colloquially called Brain water and in the Choroid plexus educated. Each ventricle has a delimited area on its inner wall Vein braid. The tangle of vessels represents a so-called Ultrafiltrate of the blood by drawing the blood plasma carefully filtered becomes. Round 600 milliliters Liquor are produced daily in the plexus. Most substances cannot cross the blood-liquor barrier between capillary blood and liquor. For oxygen, carbon dioxide and water, however, it is permeable.

Without continuous resorption (re-absorption) of the nerve fluid into the bloodstream, the CSF space would enlarge and lead to a massive increase in pressure within the brain and spinal canal. The liquor flows out of the one hand into the spinal canal and on the other hand into the outer liquor space between the meninges.
The middle meninges has protuberances that too Villi to be named. They absorb the liquor and channel it into the Veins the outer meninges and into the Lymphatics further. This prevents an increase in intracranial pressure and ensures that the liquid is exchanged up to four times a day.

Please also read our article on this Nerve fluid (liquor)

Enlargement of the cerebral ventricles

A pathological enlargement or enlargement of the cerebral ventricle is colloquially called a water head (more precisely: "Hydrocephalus"). Internal hydrocephalus is an expansion of the internal liquor space (within the brain). External hydrocephalus is an enlargement of the external fluid space (between the meninges).

Hydrocephylus internus usually arises as a result of an obstruction to drainage. Causes can be tumors, bleeding and inflammatory processes. So-called Colloid cysts are among the most common reasons for CSF congestion in the ventricular system. These benign masses grow in the third ventricle. If you lie down in front of the interventricular hole, the liquor drainage is no longer guaranteed. Symptoms of colloid cysts include vomiting, headache, and imbalance. In the worst case, they cause an increase in intracranial pressure that can be life-threatening.

Expansion of the outer and inner CSF space is also a possible consequence when the Resorption villi. A resorption disorder also leads to an increase in intracranial pressure.
Another cause of one of the ventricles is one increased liquor production, for example in the context of inflammation. If the enlarged cavities are fully connected to one another and if there is no increased intracranial pressure, one speaks of Normal pressure hydrocephalus. The following symptoms are typical: urinary incontinence, gait disorders and dementia.

Please also read our article on this Increased intracranial pressure

Enlargement of the cerebral ventricles in the baby

An expansion of the liquor spaces can also occur in babies. Such a "water head" (Hydrocephalus) is due to a prevailing imbalance between production and absorption of the liquor. On average, it affects 1 in 1000 babies. Congenital hydrocephalus can have various causes. Possible reasons are an overproduction, a resorption disorder in the area of ​​the villi or an outflow obstacle in the area of ​​the ventricular system.
The symptoms of a "water head" in babies are different from those in adults. In newborns, the fontanelles between the large cranial bones are not yet closed, so that the increase in pressure inside the brain can find its way out. The skin may appear shiny, the veins are congested, and the fontanelles bulging. Furthermore, the babies often stand out because of their greatly enlarged skull. There are also behavioral problems, such as indifference and loss of appetite. One therapy option for childhood hydrocephalus is a so-called Shunt attachment, in which an artificial drainage possibility for the liquor into the abdomen is created.
Please also read our article on this Head of water in the baby

Bleeding into the cerebral ventricle

Bleeding in the cerebral ventricles can occur spontaneously. Bleeding in the brain tissue usually breaks into the ventricular spaces, which usually has a poor prognosis for the patient. The direct consequence is a resorption disorder of the liquor with resulting Increase in intracranial pressure.
Cerebral hemorrhage (in brain tissue) often appear suddenly and apparently without a direct cause, for example through the rupture of an enlarged brain vessel (Aneurysm). Vascular deposits are associated with this clinical picture high blood pressure or vascular diseases such as atherosclerosis.
Inflammation or a tumor can also cause cerebral haemorrhage. In any case, it must be prompt intensive care treatment respectively. Cerebral hemorrhages in the brain tissue are a life-threatening emergency!
Please also read our article on this Cerebral hemorrhage