Within the mind, you will find four hollow chambers called ventricles. Two of those are rather big – the left and right lateral ventricles. Both are smaller – the 3rd ventricle and the 4th ventricle. Furthermore, there are narrow passages that connect one ventricle into another. Lastly, in addition, there are passageways that lead from the 4th ventricle from the mind and in the subarachnoid space. That’s a distance which surrounds the whole mind and encompasses the whole spinal cord. Every one of those ventricles, passageways, and spaces are filled up with a special fluid called cerebrospinal fluid. This fluid is continuously moving.
It starts in one of the ventricles. Situated inside every one of the four ventricles is a construction called a choroid plexus. A vital part of the choroid plexus is a streamlined network of blood vessels. The operation of the choroid plexus is to eliminate fluid from the blood within the capillaries and put that fluid within the ventricle. After the fluid is within the ventricle, it’s called cerebrospinal fluid. This fluid then flows throughout the passageways between ventricles and throughout the passageways that leave the mind and take the CSF to the subarachnoid space. Once there, it flows around the whole mind and the whole spinal cord.
Ultimately the fluid passes tiny structures called arachnoid villi. The role of these structures is to reunite the cerebrospinal fluid into the blood. In all, approximately one pint of fluid daily leaves the bloodstream by means of the choroid plexuses and contributes into the bloodstream by way of the arachnoid villi. The function of the cerebrospinal fluid is 3 fold. Due to its existence across the mind and spinal cord, it acts as a cushion, preventing this mind and spinal cord in bumping against the skull or vertebrae. It also can help to provide nutrients to eliminate wastes from the cells of the mind and spinal cord.
And lastly, this chemical composition of this CSF provides this proper environment necessary for the nervous tissue of the mind and spinal cord to role properly. Preferably, the amount of fluid returned into the bloodstream by this arachnoid villi should equal this amount of fluid removed from the bloodstream by the choroid plexuses. If something should happen to interfere with the reunite of CSF into this blood, this amount of fluid present in this ventricle, passageways, and subarachnoid distance will be greater than normal. Such a condition is called hydrocephalus. Hydro is in the Greek word for water and falls is in the Greek word for head.
Thus, hydrocephalus literally means waterhead. There are very different types of hydrocephalus. When mature adults develop hydrocephalus, it’s generally the type called normal pressure hydrocephalus.