CSF Full Form
What is the full form of CSF ?
CSF stands for Cerebrospinal fluid. It is a colorless, watery fluid that flows in the brain and spinal cord. This fluid acts as a cushion for the brain and spinal cord. The normal amount of CSF in adults is 150 ml. An increase in CSF amount may be an indication of several brain diseases, such as a tumor or obstruction. CSF analysis is done in many cases to assess any abnormality or pathology. For CSF analysis, we collect a sample from the lumbar region, and this procedure is known as a lumbar puncture. The normal pressure of CSF is 5-20 mmHg. Increased CSF pressure may contribute to increased intracranial pressure. Hydrocephalus is a disease condition in the CSF that increases by several folds. To know more about CSF, its characteristics, and other features, continue reading this article.
What is CSF?
The expanded form of CSF is cerebrospinal fluid. It is fluid in the central nervous system, formed by the choroid plexus in the ventricles of the brain. Ventricles are hollow spaces lined by the choroid plexus. This fluid is present in the subarachnoid space in the brain and spinal cord.
Characteristics of CSF
The following are some of the important properties of CSF:
CSF is a colorless fluid, and its color changes in pathological conditions. Its color may turn orange in cases of severe hemolysis; brown or dark colored CSF is seen in jaundice or meningeal melanoma; and green CSF is seen in the condition of hyperbilirubinemia.
The specific gravity of CSF is 1.004 - 1.007.
CSF is slightly alkaline.
CSF is clear and transparent in normal conditions, but in an abnormal condition, it becomes turbid. For example, in bacterial meningitis, CSF becomes cloudy and turbid.
Formation and circulation of the brain
CSF is formed in the choroid plexus in the ventricles of the brain. This fluid is created by selective ultrafiltration of plasma combined with selective sodium and chloride secretion.
The choroid plexus is formed by ependymal cells and mitochondria.
It is a filtrate of plasma in which red blood cells are not present. CSF has a very low protein and glucose content when compared to plasma in blood. Whereas sodium and chloride are present in high amounts compared to blood
The daily rate of production of CSF is 750mL.
There are two lateral ventricles present in the diencephalon, one third ventricle present between the two thalami, and a fourth ventricle present in the pons and upper part of the medulla.
CSF circulation begins in the lateral ventricles. CSF passes to the third ventricle through the interventricular foramen, also known as the foramen of Monro. From the third ventricle, CSF passes to the fourth ventricle through the cerebral aqueduct. Through the foramen of luschka and foramen of magendie CSF drain out of the fourth ventricle into subarachnoid space.
CSF absorbs through arachnoid granulation into the bloodstream in the superior sagittal sinus.
If the pressure in CSF is higher than venous pressure, it will flow into blood, but when CSF pressure is lower than blood pressure, it does not move into CSF because arachnoid granulations are single-side valves; these valves do not allow blood movement into CSF.
Function of the CSF
The following are some of the important functions of CSF:
It acts as a shock- absorbing fluid, protects the brain, and also reduces the weight of the brain.
This fluid also reduces the overall weight of the brain. The actual weight of the brain is 1500 g, but due to the buoyancy of the CSF, this weight feels like only 25g.
It provides nutrition to brain tissues. Glucose, protein, and various electrolytes, such as sodium chloride. All these components are necessary for brain growth and development.
It also contains various immunoglobulins, which are responsible for maintaining the immune system.
CSF also removes water from brian produced during brian metabolism.
What is CSF analysis and why is it done?
CSF analysis is the process of analyzing CSF for any abnormalities through various tests. These tests are used to diagnose any disease of the brain or spinal cord. Various things are diagnosed in this test:
Bleeding: The red appearance of CSF may indicate bleeding in the brain.
Brain tumors: this test also helps in the diagnosis of brain tumors.
Autoimmune disorder: Several autoimmune disorders, such as multiple sclerosis and Guillain-Barre syndrome, can be diagnosed with the help of this test.
Infectious disease: many infectious diseases, such as tuberculosis, meningitis, and encephalitis, can be diagnosed by analyzing CSF.
CSF disorder
Some disorders of the brain and spinal cord due to abnormal CSF are hydrocephalus, meningitis, syringomyelia, etc.
Hydrocephalus may be congenital or acquired. In this condition, CSF builds up in large amounts and exerts pressure on brain tissue damaging them. This can cause bulging of the head, headaches, blurred vision, an abnormal gait, etc. This may be due to overproduction of CSF, a tumor of the choroid plexus, abnormal or improper drainage of CSF, or blockage of any foramen. It may also occur in any infectious disease, such as the mumps or rubella.
Meningitis: It is defined as inflammation of the meningeal, or brain covering. It may be due to bacterial, viral, or fungal infections.
Syringomyelia is a disorder of the spine. which fluid-filled cyst forms in the spinal cord. With time, this cyst gets bigger, which may later compress the nerves and cause spinal damage.
Frequently Asked Questions (FAQs)
The process of taking out CSF from the spinal cord is known as lumbar puncture. In this test, a needle is inserted between the 3rd and 4th lumbar spines and CSF is taken out. Yes, it is a painful procedure.
Patients with low CSF can experience significant memory loss, whereas high levels of CSF may confuse.
There are 5 cells per mm3 in the CSF of adults and children.
Yes, increased CSF pressure can increase intraocular pressure, which can cause blurred vision.
Yes, MRI can detect CSF leakage and its causes.