The choroid plexuses are specialized structures of the central nervous system that perform vital functions in the brain. Located in the cerebral ventricles, these plexuses are responsible for producing cerebrospinal fluid, a clear liquid that acts as a shock absorber and protector of the brain and spinal cord. In addition to their role in producing cerebrospinal fluid, the choroid plexuses also play a crucial role in removing metabolic waste and regulating the brain's chemical environment.
Anatomy of the Choroid Plexuses
The choroid plexuses are specialized vascular structures found in the cerebral ventricles, specifically in the roof of the third and fourth ventricles, as well as in the walls of the lateral ventricles. They are formed by a highly vascularized epithelial tissue covered by a layer of specialized epithelial cells.
Histological Structure
At the histological level, the choroid plexuses present a characteristic structure. They are formed by a simple cuboidal or cubic epithelium that lines the blood capillaries. These epithelial cells are joined by tight junctions that form a semipermeable barrier that regulates the entry of substances from the bloodstream into the cerebrospinal fluid.
In addition to the epithelial cells, the choroid plexuses contain ependymal cells, whose cylindrical processes maintain contact with the cerebrospinal fluid and participate in the regulation of its content. The choroid plexuses receive an abundant blood supply through the choroid vessels, which allows them to perform their functions of production and filtration of cerebrospinal fluid.
Innervation and Vascularization
The choroid plexuses They are supplied by a vascular network that comes from the choroidal arteries, branches of the internal carotid artery, and the posterior cerebral artery. This abundant vascular network is crucial for the proper functioning of the choroid plexuses, since it provides the blood supply necessary for the production of cerebrospinal fluid.
As for innervation, the choroid plexuses receive sympathetic and parasympathetic fibers. that regulate the secretion and absorption of cerebrospinal fluid. These nerve fibers help maintain balance in the production and reabsorption of fluid circulating through the ventricular system.
Functions of the Choroid Plexuses
The choroid plexuses perform several critical functions for the proper functioning of the central nervous system:
Production of Cerebrospinal Fluid
One of the main functions of the choroid plexuses is the production of cerebrospinal fluid, a clear, watery liquid that fills the ventricles brain and the subarachnoid space that surrounds the central nervous system. This substance acts as a shock absorber that protects the brain and spinal cord from impacts and injuries, in addition to providing a means for the elimination of metabolic waste and the distribution of nutrients and hormones.
Filtration and Regulation of the Environment Cerebral
The choroid plexuses also participate in filtering and regulating the chemical environment of the brain. Through the blood-brain barrier and the blood-brain barrier, the choroid plexuses select and regulate substances that are incorporated into the cerebrospinal fluid, thus maintaining a stable internal environment and protecting the brain from toxins and harmful substances.
Elimination Metabolic Waste
Another important function of the choroid plexus is the removal of metabolic waste and unwanted substances from the cerebrospinal fluid. These wastes are transported from the brain and spinal cord to the cerebrospinal fluid by the choroid plexuses, where they are subsequently eliminated from the central nervous system through the blood circulation or lymphatic system.
Pathologies of the Choroid Plexuses
Although the choroid plexuses are resilient and vital structures for the proper functioning of the brain, they can be affected by various pathologies that compromise their function and cause disorders in the ventricular system and the production of cerebrospinal fluid. Some of the most common pathologies that affect the choroid plexuses include:
Hydrocephaly
Hydrocephalus is a condition characterized by the excessive accumulation of cerebrospinal fluid in the cerebral ventricles, which causes an increase in intracranial pressure and can cause brain damage. The choroid plexuses may be involved in the etiology of hydrocephalus, either due to an excess in the production of cerebrospinal fluid or due to an obstruction in its circulation and reabsorption.
Tumors of the Choroid Plexus
Tumors of the choroid plexuses are rare neoplasms that can develop in these structures. These tumors can interfere with the production and circulation of cerebrospinal fluid, causing symptoms such as headache, vision changes, and alterations in balance and gait. Treatment of choroid plexus tumors may involve surgery, radiotherapy and chemotherapy, depending on the nature and extent of the tumor.
Inflammation of the Choroid Plexuses
Inflammation of the choroid plexus Choroid plexuses, known as choroiditis, can be caused by viral, bacterial or autoimmune infections that affect these structures. Choroiditis can cause an increase in the production of cerebrospinal fluid, alterations in the chemical composition of the fluid and obstructions in the ventricular circulation, which can lead to hydrocephalus and other neurological disorders.
Congenital Malformations
Some congenital malformations can affect the choroid plexuses and cause anomalies in their structure and function. These malformations can include choroid cysts, epithelial dysplasias and disorders in vascular development, which can compromise the production and regulation of cerebrospinal fluid and lead to complications in the central nervous system.
Traumatic Injuries
Traumatic head injuries can affect the choroid plexuses and cause hemorrhages, bruises or lacerations in these structures. Injuries to the choroid plexuses can alter the production and circulation of cerebrospinal fluid, which can lead to complications such as traumatic hydrocephalus and cerebral edema. Treatment of traumatic injuries to the choroid plexuses may require intracranial pressure control measures, reconstructive surgery, and neurological rehabilitation.
Conclusions
The choroid plexuses are key anatomical and functional structures in the central nervous system, responsible for the production, filtration and regulation of cerebrospinal fluid. Its proper functioning is essential to maintain a stable internal environment in the brain and spinal cord, protecting these organs from damage and disorders.
The study of the choroid plexuses and their pathologies is essential to better understand diseases. that affect the ventricular system and cerebrospinal fluid, as well as to develop therapeutic strategies aimed at preserving the function of these structures. With greater knowledge of the anatomy, functions and pathologies of the choroid plexuses, health professionals can improve the care and treatment of neurological disorders associated with these important structures.