Hydrocephalus

Hydrocephalus occurs when fluid accumulates in the brain. (Read about "The Brain") According to the National Institute of Neurological Disorders and Stroke (NINDS), hydrocephalus was once known as "water on the brain." The "water" is actually cerebrospinal fluid (CSF) - a clear fluid surrounding the brain and spinal cord. The buildup of the fluid results in pressure on the brain that can cause a number of problems.

According to NINDS, there are two main types of hydrocephalus:

• Congenital hydrocephalus - Congenital hydrocephalus is present at birth and may be caused by either environmental influences during fetal development or genetic predisposition. (Read about "Genetics") Aqueductal stenosis and spina bifida (Read about "Neural Tube Defects") are two examples. Hydrocephalus is believed to occur in about 2 out of 1,000 births, according to the Hydrocephalus Association (HA).
• Acquired hydrocephalus - Acquired hydrocephalus happens later in life. It can affect people of all ages. It is usually the result of injury or disease. HA says some common causes are intraventricular hemorrhage, meningitis, head trauma, vascular lesions, tumors and cysts. (Read about "Encephalitis & Meningitis" "Head Injury" "Brain Tumors" "Vascular Lesions of the Central Nervous System" "Arachnoid Cyst")

Symptoms

Symptoms of hydrocephalus vary with age, how far the condition has progressed and individual differences in tolerance to CSF. For example, an infant's ability to tolerate CSF pressure differs from an adult's. The infant skull can expand to accommodate the buildup of CSF because the fibrous joints that connect the bones of the skull have not yet closed.

In infancy, the most obvious indication of hydrocephalus is often the rapid increase in head circumference or an unusually large head size. Other symptoms may include vomiting, sleepiness, irritability, downward deviation of the eyes and seizures. (Read about "Seizures")

Older children and adults may experience different symptoms because their skulls cannot expand to accommodate the buildup of CSF. In older children or adults, symptoms may include headache (Read about "Headaches") followed by vomiting, nausea, blurred vision, double vision, problems with balance (Read about "Balance Disorders"), poor coordination, gait disturbance, urinary incontinence (Read about "Incontinence"), slowing or loss of development (Read about "Child Development"), lethargy, drowsiness, irritability, or other changes in personality, including memory loss.

There is also a condition called normal pressure hydrocephalus. Symptoms of normal pressure hydrocephalus include progressive mental impairment and dementia (Read about "Dementia"), problems with walking and impaired bladder control leading to urinary frequency and/or incontinence. (Read about "The Urinary System") The person also may have a general slowing of movements or may complain that his or her feet feel "stuck." Because these symptoms are similar to those of other disorders such as Alzheimer's disease, Parkinson's disease, and Creutzfeldt-Jakob disease (Read about "Alzheimer's Disease" "Parkinson's Disease" "Creutzfeldt-Jakob Disease"), the disorder is often misdiagnosed. Many cases go unrecognized and are never properly treated.

Doctors may use a variety of tests, including brain scans (CT and/or MRI), a spinal tap or lumbar catheter, intracranial pressure monitoring and neuropsychological tests, to help them diagnose normal pressure hydrocephalus and rule out other conditions. (Read about "CT Scan - Computerized Tomography" "MRI - Magnetic Resonance Imaging")

Treatment

NINDS and HA say hydrocephalus is most often treated with the surgical placement of a shunt system. (Read about "Neurosurgery") This system diverts the flow of CSF away from the brain to another area of the body where it can be absorbed. Another treatment, called endoscopic third ventriculostomy (ETV), is growing in popularity as an alternative treatment method for hydrocephalus, according to HA. It is used when there is an obstruction in the drainage system of CSF. It allows the fluid to bypass the obstruction and be reabsorbed.

According to NINDS, the success of treatment with shunts varies from person to person; some people recover almost completely after treatment and have a good quality of life. Early diagnosis and treatment improves the chance of a good recovery.

NINDS says hydrocephalus poses risks to both cognitive and physical development. However, many children diagnosed with the disorder benefit from rehabilitation therapies (Read about "Rehabilitation") and educational interventions and go on to lead normal lives with few limitations. Left untreated, progressive hydrocephalus is, with rare exceptions, fatal.

Related Information:

    Encephalopathy