Hydrocephalus Diagnosed in Young and Middle-Aged Adults (SHYMA)

Symptoms

Symptoms of SHYMA may include headache, subtle gait disturbance, urinary frequency, visual disturbances and some level of impaired cognitive skills that can noticeably affect job performance and personal relationships. Correct diagnosis is oftentimes delayed, as the signs, symptoms and risk factors may not be recognized.

The degree of symptoms and their resultant effect varies widely among patients. If symptoms have been present for years, the patient may be more seriously disabled. Early diagnosis can be a factor in successful resolution of symptoms.

The cause of the hydrocephalus may be congenital (present at birth with few or no symptoms); acquired, from such things as head injury or trauma, meningitis, or a brain tumor; or idiopathic (no known cause). Additionally, some people who were shunted for hydrocephalus as infants but are no longer under the care of a pediatric specialist may exhibit gradual signs of unrecognized shunt failure due to uncompensated hydrocephalus.

Diagnostics

SHYMA is diagnosed using a combination of brain scans, intracranial pressure monitoring and clinical evaluation of symptoms.

Once symptoms of gait disturbance, mild dementia or bladder control have been identified, a physician who suspects hydrocephalus may recommend one or more additional tests. At this point in the diagnostic process, it is important that a neurologist and a neurosurgeon become part of your medical team, along with your primary care physician. Their involvement from the diagnostic stage onward is helpful not only in interpreting test results and selecting likely candidates for shunting but also in discussing the actual surgery and follow-up care, as well as expectations of surgery. The decision to order a given test may depend on the specific clinical situation, as well as the preference and experience of your medical team.

These tests may include computerized tomography (CT), magnetic resonance imaging (MRI), lumbar puncture, continuous lumbar CSF drainage, intracranial pressure (ICP) monitoring, measurement of cerebrospinal fluid outflow resistance or isotopic cisternography. Neuropsychological evaluation may also be recommended.

Treatments

In many cases, prompt treatment can reverse many of the symptoms of hydrocephalus, restoring much cognitive and physical functioning. If left untreated, however, symptoms can become quite disabling, leading to severe cognitive and physical decline.

The most common treatment for SHYMA, as with all forms of hydrocephalus, is shunting.

Hydrocephalus is a chronic condition. However, with early detection, effective treatment and appropriate interventional services, the future for individuals with hydrocephalus is promising.

"Reprinted with permission of the Hydrocephalus Association. All rights reserved."

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Adult-Onset Normal Pressure Hydrocephalus

Normal pressure hydrocephalus (NPH) is an accumulation of cerebrospinal fluid that causes the ventricles in the brain to become enlarged with little or no increase in pressure. The name of this condition is misleading, however, because some patients have fluctuations of cerebrospinal fluid (CSF) pressure from high to normal to low. In most cases of NPH, it is not clear what causes the CSF pathways to become blocked.

Adult-onset normal pressure hydrocephalus describes those cases that occur in older adults (age 50 and older). The majority of the NPH population is 60 years or older.

The majority of cases of NPH are idiopathic (meaning unknown cause). In some cases, NPH can develop as the result of a head injury, cranial surgery, subarachnoid hemorrhage, meningitis, tumor or cysts, as well as subdural hematomas, bleeding during surgery, and other infections.

Symptoms

The syndrome of normal pressure hydrocephalus is usually characterized by complaints of gait disturbance (difficulty walking), mild dementia and impaired bladder control.

Gait disturbance – This can range in severity from mild imbalance to the inability to stand or walk at all. Gait is often wide-based, short-stepped, slow and shuffling. People with NPH may have trouble picking up their feet, making stairs and curbs difficult and frequently resulting in falls. They may also have difficulty turning around, and turn very slowly with multiple steps. Gait disturbance is often the most pronounced symptom and the first to become apparent.

Mild dementia — This can be described as a loss of interest in daily activities, forgetfulness, difficulty dealing with routine tasks and short-term memory loss. The cognitive symptoms associated with NPH are usually less severe than full-blown dementia, and are often overlooked for years or accepted as an inevitable consequence of aging. People with NPH do not usually lose language skills, but they may be less aware of their deficits than those around them, and may even deny that there are any problems. Not all individuals have an obvious cognitive impairment. In mildly affected cases, conversational skills may be preserved and thinking abilities may be relatively unchanged. In some cases, cognitive changes may only be detectable with formal neuropsychological testing.

Impairment in bladder control – This is usually characterized by urinary frequency and urgency in mild cases whereas a complete loss of bladder control (urinary incontinence) can occur in more severe cases. Urinary frequency is the need to urinate more often than usual, sometimes as often as every one to two hours. Urinary urgency is a strong, immediate sensation of the need to urinate. This urge is sometimes so strong that it cannot be held back, resulting in incontinence. In very rare cases, fecal incontinence may occur. Some people never display signs of bladder problems.

Because these symptoms are often associated with the aging process in general, and a majority of the NPH population is older than 60 years, people often assume that they must live with the problems and adapt to the changes occurring within their bodies.

Diagnosis

When NPH is suspected, one or more of the following tests is usually recommended to confirm the diagnosis and assess the person's candidacy for shunt treatment.

Clinical exams to evaluate symptoms – This consists of an interview and/or a physical/neurologic examination. Some common tests include discussing and observing walking and turning to determine the extent of and type of gait disturbance; assessing cognition by asking a few questions or administering a full neuropsychological evaluation to probe such qualities as attention, reaction time, memory, reasoning, language and emotional state; and verbally assessing urinary urgency and frequency or incontinence.

Brain images to detect enlarged ventricles – These commonly include magnetic resonance imaging (MRI) and computerized tomography (CT).

Cerebrospinal fluid tests (CSF) – These include lumbar punctures, known as a spinal tap, which allows an estimation of the CSF pressure and analysis of the fluid; external lumbar drainage; measurement of CSF outflow resistance; intracranial pressure monitoring; and isotopic cisternography, which involves having a radioactive isotope injected into the lower back through a spinal tap, to monitor the absorption of CSF over a period of several days.

Treatment

A shunt is the most common and usually the only available treatment for NPH. A shunt is a flexible tube placed into the ventricular system that diverts the flow of CSF into another region of the body where it can be absorbed, such as the peritoneal (abdominal) cavity or the right atrium of the heart. The shunt tube is about 1/8 inch in diameter and is made of a soft, pliable plastic that is well tolerated by our body tissues. Shunt systems come in a variety of models but have similar functional components. Catheters (tubing) and a flow-control mechanism (one-way valve) are components common to all shunts. The valve in the shunt maintains the CSF at normal pressure within the ventricles.

The surgical placement of a shunt, which is performed by a neurosurgeon, is a relatively short and uncomplicated procedure. The patient is brought to the operating room and is placed under general anesthesia. To ensure cleanliness, a small region of the scalp may be clipped or shaved, and, for a ventriculoperitoneal shunt, the entire area from the scalp to the abdomen is scrubbed with an antiseptic solution. Sterile drapes are placed over the patient. Incisions are made in the head and abdominal areas. The shunt tube is passed beneath the skin, in the fatty tissue that lies just below the skin. A small hole is made in the skull, and the membranes between the skull and brain are opened. The ventricular end of the shunt is gently passed through the brain into the lateral ventricle. The abdominal (peritoneal) end is passed into the abdominal cavity through a small opening in the lining (peritoneum) of the abdomen. This is where the CSF will ultimately be absorbed. The incisions are then closed. When the procedure is completed, sterile bandages may be applied to the incisions and the patient is taken to the recovery room where the anesthesia is allowed to wear off.

There are many unknowns surrounding the diagnosis and treatment of normal pressure hydrocephalus. Although the success rate for shunting can be as high as 80 percent when the cause of hydrocephalus is known, the chance for a complete reversal of symptoms or marked improvement is less predictable. However, NPH is not a hopeless condition. Advanced technology is continually introduced and developed. Adults diagnosed with normal pressure hydrocephalus, and their families, should be encouraged to ask questions, gather information and network with others.

"Reprinted with permission of the Hydrocephalus Association. All rights reserved."

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A Team Approach

The team of experts at the Adult Hydrocephalus Center is actively involved in research, patient/family education and patient advocacy efforts to provide more funding for hydrocephalus research and treatment.

Michael A Williams, MD, is the medical director of The Sandra and Malcolm Berman Brain & Spine Institute, director of the Adult Hydrocephalus Center, and codirector of the Center for Gait & Mobility. A graduate of the Indiana University School of Medicine, he completed a transitional internship at Methodist Hospital of Indianapolis, a neurology residency at Indiana University Medical Center, and a fellowship in neurosciences critical care at Johns Hopkins Hospital. Prior to joining LifeBridge Health, he was an attending physician in the Neurosciences Critical Care Unit at Hopkins for 16 years, where he founded the hospital's Adult Hydrocephalus Program. Dr. Williams is board certified in neurology. Widely sought as a lecturer and educator, he serves on the Medical Advisory Board of the Hydrocephalus Association and has been active on numerous advisory committees and panels with a focus on ethics, organ donation, and end-of-life-care, including the Ethics, Law, and Humanities Committee of the American Academy of Neurology, the JHH Ethics Committee (which he co-chaired), the Sinai Hospital Ethics Committee, and the Advisory Committee on Organ Transplantation of the US Department of Health and Human Services.

Robin K Wilson, PhD, MD, is the associate director of the Adult Hydrocephalus Center. After earning a doctorate of philosophy in genetics at Cornell University and serving on the faculty of Cornell and the University of Maine, she earned a medical degree at the University of Pittsburgh School of Medicine. She then interned at the Hopkins Bayview Medical Center and completed a neurology residency at JHH, where she also received fellowship training in adult hydrocephalus. Dr. Wilson is certified in neurology by the American Board of Psychiatry and Neurology and is a member of the American Academy of Neurology.

Carol Wamboldt, MS, CRNP, CNRN, is the nurse practitioner for the Adult Hydrocephalus Center. She completed her nursing degree at James Madison University and her graduate studies at the University of Maryland, specializing in adult medicine. Prior to joining LifeBridge Health, Ms. Wamboldt was a nurse on the Neuroscience Critical Care Unit at Johns Hopkins Hospital and a nurse practitioner with the neuromuscular division at the University of Maryland.

For more information about the Center for Memory and Brain Health, call 410-601-WELL (410-601-9355).

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