Cerebral spinal fluid, or CSF, is a clear fluid that circulates constantly around the brain and spinal cord. Blood does not directly reach brain cells. Instead, CSF transports nutrients from the blood to brain cells, and takes waste products away from brain cells and deposits them back into the blood. When a person accumulates too much CSF in part or all of the brain, it results in a condition called hydrocephalus. Hydrocephalus can cause severe headaches, dizziness, visual disturbances, loss of balance and memory loss. MayoClinic.com says that, in the majority of cases, the cause is unknown. Still, some triggers are well understood.
Traumatic Brain Injury
According to the National Institutes of Health, most cases of hydrocephalus occur not because the body is producing too much CSF, but because the natural circulation and reabsorption of CSF through the brain is blocked. The brain has four chambers called ventricles that are normally filled with fluid. CSF circulates between the ventricles and into the space surrounding the brain along narrow channels. Pressure from swelling, a normal response to traumatic head injuries, can squeeze the chambers shut, blocking the proper flow of CSF.
Brain Hemorrhage
Brain hemorrhage caused by a ruptured blood vessel in the brain triggers swelling. This swelling can squeeze the passages between ventricles and the space around the brain. This blocks circulation between the chambers and causes a dangerous buildup of CSF behind the blockage.
Bacterial Infections
Bacterial infections of the brain or surrounding tissues can block absorption of CSF. Hydrocephalus may develop because the body is producing CSF at a normal rate, but absorbing it at a slower than normal pace. This is most common with meningitis, and more rarely, with an infection known as cysticercosis.
Brain Tumor
Tumors within the brain, malignant or benign, can trigger hydrocephalus. A growing tumor may put pressure on the passages where CSF travels, causing a blockage. Depending on location, a tumor can also block normal reabsorption of CSF. Rarely, a tumor develops that can cause the body to produce more CSF than it can absorb.
Congenital Malformations
Some children are born with malformations of the brain that lead to hydrocephalus. Several different malformations have been identified and studied. While these conditions once had a very high mortality rate, the Hydrocephalus Association reports that advances in recent years have drastically improved the survival rate of newborns with hydrocephalus due to unusually formed brain structures.
Spina Bifida
Babies with the developmental disorder known as spina bifida often develop hydrocephalus. This condition seems to block proper reabsorption of CSF.
