What is Hydrocephalus?
Hydrocephalus is a condition in which there is an excessive accumulation of fluid within the skull. You may have heard hydrocephalus referred to as "water on the brain," in part because because "hydro" means water and "cephalus" means head. The term "water on the brain" isn't actually correct, though, as the fluid isn't water. It's actually a very important liquid called Cerebrospinal fluid.
Cerebrospinal fluid, or CSF, is a clear fluid that surrounds the spinal cord and brain. A few of the functions of CSF include acting as a shock absorber, transporting nutrients, removal of waste, and regulating pressure in the brain. The body continuously produces and absorbs CSF. If anything affects the production or absorption process, it can lead to an imbalance. Pressure on the brain may also occur if the normal flow of CSF is interrupted, as this can create a buildup of CSF.
An excess of pressure on the brain can be very harmful. If left untreated, hydrocephalus may cause permanent brain damage or even death. However, with appropriate treatment, most patients are able to lead normal lives with few limitations.
Hydrocephalus can occur in patients of any age from infants to the elderly. There are different types and/or classifications of hydrocephalus.
- Congenital Hydrocephalus: This type is present at birth and is due to genetic abnormalities or events during fetal development.
- Acquired Hydrocephalus: This type occurs after birth and can affect individuals of any age. It's the result of a disease or an injury.
- Communicating Hydrocephalus: Here the CSF can flow, or "communicate," between open ventricles in the brain, but its flow is blocked after it leaves the ventricles.
- Obstructive Hydrocephalus: This is also known as non-communicating hydrocephalus. Here there's a blockage that prevents the flow of CSF between the ventricles in the brain.
- Normal Pressure Hydrocephalus: This type is more common among the elderly, although it can affect patients of any age. Some of the common causes of Normal Pressure Hydrocephalus include trauma to the head, subarachnoid hemorrhage, infection, tumor or surgical complications.
- Hydrocephalus Ex-vacuo: This type occurs primarily in adults. It is generally the result of stroke or trauma.
What Causes Hydrocephalus?
The cause of hydrocephalus can vary depending on which type it is. Some causes of hydrocephalus are:
- Genetic defects or problems during fetal development
- Head trauma
- Subarachnoid hemorrhage
- Infections that affect the central nervous system, such as encephalitis or meningitis
- Tumors that affect the brain, spinal cord, or elsewhere in the central nervous system
What are the Symptoms of Hydrocephalus?
Symptoms of hydrocephalus vary depending on the cause of the CSF buildup, the extent of any brain damage, and the patient's age. Some common symptoms seen in patients with this condition may include:
- Nausea and vomiting
- Excessive sleepiness
- Personality changes
- Cognitive changes, such as problems with memory or the ability to think
- Vision problems, such as sudden blurry vision or uncontrolled eye movement
- Balance or coordination problems
How is Hydrocephalus Diagnosed?
A physician may perform following to diagnosis hydrocephalus:
- Medical history: Discussing current symptoms and medical history, including previous head injuries and surgeries, as well as existing conditions or diseases that may affect the brain.
- Physical and neurological examination: Assessing cognitive function, gait or walking, and balance.
- Imaging studies: Patients suspected of having hydrocephalus will undergo imaging studies, such as MRI or CT scans, of their head.
- Diagnostic procedures: Patients suspected of having hydrocephalus may also undergo a procedure to drain some cerebral spinal fluid. A procedure called a lumbar puncture, also known as a spinal tap, will be required to accomplish this. The patient will be observed after the drainage to determine if their symptoms improve.
How is Hydrocephalus Treated?
Without treatment, symptoms often continue to get worse and can lead to death. Surgical treatment improves symptoms in many patients; however, not all patients see improvement in their symptoms. There is no way to accurately predict which patients will improve with surgery, although those with minimal symptoms generally have the best outcomes. If a patient's symptoms improve with cerebral spinal fluid drainage, then surgery is generally recommended.
There are several surgical procedures to treat hydrocephalus:
- Removal of the obstruction: The goal of this procedure is to remove the tumor or other object causing the accumulation of cerebrospinal fluid.
- Ventricular shunt surgery: The goal of this procedure is to enable the excess CSF to flow out of the ventricle into another region of the body where it can be absorbed. A thin, soft tube called a shunt is placed in the ventricle to accomplish this. The shunt has a one-way valve that regulates the CSF flow.
- Endoscopic third ventriculostomy: This is a minimally invasive procedure where the surgeon makes a small hole in bottom of a ventricle to create a new pathway through which CSF can flow.