What is Cerebrospinal Fluid?
CSF is a colourless fluid that circulates around the surface of the brain and the spinal cord. CSF serves as a cushion for the brain and the spinal cord. It is also plays a role in immune and metabolic functions. The normal CSF is 150 ml in the ventricles and the subarachnoid space.
The Normal Flow of CSF
Cerebrospinal fluid or CSF is formed in the choroid plexus. From the lateral ventricles, CSF flows through two passageways into the third ventricle at the foramen of Monro. From the third ventricle it flows down a long, narrow passageway (the aqueduct of Sylvius) into the fourth ventricle. From the fourth ventricle the CSF drains in the openings (foramina) into the subarachnoid space surrounding the brain and spinal cord. CSF is absorbed in the arachnoid villi. Blockage of CSF flow anywhere in the ventricular system produces obstructive hydrocephalus.
2 Kinds of Hydrocephalus
Communicating hydrocephalus is caused by faulty absorption of CSF. No obstruction or blockage in the ventricular system occurred.
Noncommunicating hydrocephalus is caused by obstruction or blockage caused by tumors, blood clot, infection, or abnormal fetal development.
The medical treatment for hydrocephalus is shunting. In atrioventricular shunting, CSF drains into the right atrium of the heart from the lateral ventricle, bypassing the obstruction. Ventriculoperitoneal shunting on the other hand, transports excess fluid from the lateral ventricle into the peritoneal cavity.
Hydrocephalus Pathophysiology and Schematic Diagram
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