Hovedventrikler

Hovedventrikler, often translated as cerebral ventricles, are a series of interconnected cavities within the brain that are filled with cerebrospinal fluid. These ventricles play a crucial role in the production, circulation, and absorption of cerebrospinal fluid, which acts as a cushion for the brain, transports nutrients, and removes waste products.

There are four main ventricles in the human brain. The largest are the two lateral ventricles, located deep within the cerebral hemispheres. Each lateral ventricle has a C-shape and comprises a body, anterior horn, posterior horn, and inferior horn. Connected to the lateral ventricles is the third ventricle, a midline structure situated between the two thalami. A narrow channel called the cerebral aqueduct passes through the midbrain, connecting the third ventricle to the fourth ventricle. The fourth ventricle is a diamond-shaped cavity located between the pons, medulla oblongata, and cerebellum.

Cerebrospinal fluid is produced primarily by specialized structures called the choroid plexuses, which are found within each ventricle. From the ventricles, the fluid flows through a series of openings into the subarachnoid space, the space between the arachnoid mater and the pia mater, which surrounds the brain and spinal cord. The fluid is then reabsorbed back into the bloodstream through arachnoid villi, specialized projections of the arachnoid mater that protrude into the dural venous sinuses. The continuous circulation of cerebrospinal fluid is vital for maintaining a stable internal environment within the central nervous system. Disruptions to this system, such as blockages in the flow of cerebrospinal fluid, can lead to conditions like hydrocephalus, characterized by an abnormal accumulation of fluid and increased pressure within the skull.