Normal Pressure Hydrocephalus: symptoms, treatment with and without shunt

Medically reviewed: 24, January 2024

Normal Pressure Hydrocephalus: A Misunderstood and Underdiagnosed Condition

NPH is a medical abbreviation for Normal Pressure Hydrocephalus, a condition of the nervous system that is distinguished by the buildup of cerebrospinal fluid within the brain. This occurs when there is an imbalance in the production and absorption of cerebrospinal fluid, leading to an abnormal accumulation and subsequent pressure on the brain tissues, leading to impairments in motor functions, cognitive abilities, and urinary control.

It usually happens when excess cerebrospinal fluid (CSF) gathers in the ventricles, the fluid-filled chambers of the brain, and causes them to enlarge. Unlike other types of hydrocephalus, NPH is not associated with high pressure in the CSF, but rather with normal or slightly elevated pressure. This makes it difficult to diagnose and treat, and often leads to misdiagnosis as other neurological disorders. Some examples of neurological conditions include Alzheimer’s disease, various types of stroke, and also Parkinson’s disease.

Normal pressure hydrocephalus is a typically rare condition, but its incidence increases with age. It is estimated that about 1.5% of the elderly population may have NPH, but many cases remain undetected or untreated. NPH can have a significant impact on the quality of life and independence of the affected individuals and their caregivers. However, with early diagnosis and appropriate treatment, many patients can improve their symptoms and regain their function.
In this informative article, we will delve into a comprehensive discussion about the various factors contributing to normal pressure hydrocephalus, its telltale signs and manifestations, the methodologies employed to diagnose this condition, and the plethora of treatment options available to effectively manage and alleviate its effects and provide some tips for living with this condition.

What causes normal pressure hydrocephalus?

The exact cause of NPH is not fully understood, but it is believed to involve a disturbance in the production, circulation, or absorption of CSF.

Cerebrospinal fluid (CSF) is a transparent liquid that envelops and safeguards the brain and spinal cord, providing vital nourishment and cushioning, and carries nutrients and waste products. Normally, the amount of CSF in the brain is balanced by the rate of its production and absorption. However, in normal pressure hydrocephalus, something interferes with this balance, and causes CSF to accumulate in the ventricles.

There are two main types of NPH:

• idiopathic
• and secondary.

Idiopathic normal pressure hydrocephalus means that the cause is unknown, and it accounts for about 50% of the cases. Secondary normal pressure hydrocephalus means that the condition is caused by another factor, such as:

• Head injury
• Brain infection
• Brain hemorrhage
• Brain tumor
• Brain surgery

These factors may damage the brain tissue or the blood vessels, and impair the CSF flow or absorption. However, not everyone who has these factors develops NPH, and the time between the triggering event and the onset of NPH can vary from months to years.

What are the symptoms of normal pressure hydrocephalus?

The symptoms of NPH are often gradual and progressive, and may vary from one patient to another:

Unsteady gait

Gait disturbance is the primary and most distinguishable symptom associated with NPH, encompassing challenges in walking, maintaining balance, and coordinating movements. People with normal pressure hydrocephalus may have a slow, shuffling, or wide-based gait, and may feel like their feet are stuck to the floor. They may also have trouble turning, starting, or stopping, and may fall frequently.

Cognitive impairment

This symptom refers to problems with memory, attention, concentration, and reasoning. Patients with NPH may have difficulty remembering recent events, following instructions, finding words, or performing tasks. They may also have changes in personality, mood, or behavior, such as apathy, irritability, or depression.

Urinary incontinence

This symptom refers to loss of bladder control, which may manifest as urgency, frequency, or leakage of urine. People with normal pressure hydrocephalus may also have difficulty initiating or stopping urination, or may have nocturia, which is the need to urinate at night.

These symptoms can be remembered with the mnemonic “wet, wobbly, and wacky”. However, not all patients with NPH have all three symptoms, and some may have other symptoms, such as intense headaches, feeling of nausea, sometimes – vomiting, or vision problems.

How is normal pressure hydrocephalus diagnosed?

The diagnosis of NPH can be challenging, as there is no single test that can confirm or rule out the condition. The diagnosis is based on a combination of clinical evaluation, imaging studies, and CSF tests.

Clinical evaluation

The clinical evaluation involves a comprehensive medical background, an in-depth physical assessment, as well as a thorough evaluation of the neurological system. The medical history aims to identify any possible causes or risk factors for NPH, such as head trauma, infection, or surgery. The physical examination assesses the general health and vital signs of the patient, and looks for signs of increased intracranial pressure, such as papilledema, which is swelling of the optic nerve.

Neurological examination

The neurological examination is a comprehensive assessment that encompasses various aspects of the patient’s mental and physical well-being. It involves evaluating their mental status, checking condition of cranial nerves, evaluating motor function, sensory function, reflexes, and coordination. One of the primary goals of this examination is to determine the presence and severity of the triad of symptoms, which includes gait disturbance, and incontinence of the urine as a very clear sign of NPH, and cognitive impairment. To further investigate and understand the underlying causes of these symptoms.

Imaging to diagnose NPH

The utilization of diagnostic techniques like computed tomography (CT) or another diagnostics method – magnetic resonance imaging (MRI), to capture detailed images of the brain. These advanced imaging techniques provide valuable insights into the structural and functional aspects of the brain, which can show the size and shape of the ventricles and the surrounding brain tissue.

One characteristic observation in individuals with normal pressure hydrocephalus is the presence of ventricles that are larger than what would be expected in relation to the enlargement of the cortical sulci. Additionally, there is often noticeable widening of the Sylvian fissure and a clustering of brain tissue at the vertex. This specific pattern is referred to DESH, also known as disproportionately enlarged subarachnoid space hydrocephalus, is a medical condition characterized by an abnormal enlargement of the subarachnoid space within the brain. It serves as a useful diagnostic tool in differentiating NPH from other conditions that may cause hydrocephalus.

However, imaging studies alone are not sufficient to diagnose NPH, as some people may have enlarged ventricles without symptoms, and some people may have symptoms without enlarged ventricles.

CSF tests (cerebrospinal fluid tests)

The CSF tests involve the measurement of the CSF pressure and the removal of a small amount of CSF from the lower back, which is called a lumbar puncture or spinal tap. The cerebrospinal fluid pressure is usually normal or slightly elevated in normal pressure hydrocephalus, but it can vary depending on the posture, activity, and breathing of the patient.

The removal of CSF can have two purposes:

• to analyze the CSF for signs of infection, inflammation, or bleeding,
• and to observe the effect of CSF drainage on the symptoms of normal pressure hydrocephalus.

The second procedure mentioned is known as a CSF tap test. This procedure entails the extraction of approximately 30 to 50 milliliters of cerebrospinal fluid from the patient. Subsequently, the patient’s gait, cognitive abilities, and bladder function are carefully evaluated both prior to and following the completion of the cerebrospinal fluid tap test.

A positive CSF tap test means that the patient shows improvement in one or more of these domains after the CSF drainage, and it suggests that the patient may benefit from a surgical treatment for NPH. However, the CSF tap test is not always reliable, as some patients may have a temporary or false improvement, and some patients may have no improvement despite having NPH.

Normal pressure hydrocephalus treatment

The primary method of addressing NPH involves undergoing a surgical procedure which involves the insertion of a tube, known as a shunt, in the brain. This tube is typically placed within a ventricle in the brain and is then threaded beneath the skin, starting from the head, passing through the neck, and continuing down to the chest and ultimately reaching the abdomen.

By employing this shunt, any surplus cerebrospinal fluid (CSF) present in the brain is able to exit through it and make its way into the abdomen, where it is subsequently absorbed by the body.

The shunt has a valve that regulates the amount and direction of the CSF flow, and it can be adjusted externally by a magnet. It remains in position as long as there is an excess amount of cerebrospinal fluid that brain contains.

Sometimes the shunt surgery is the only treatment that can potentially reverse the symptoms of NPH, and it can improve the quality of life and independence of the patients. However, the surgery is not without risks, and it does not work for everyone. Some of the possible complications of the shunt surgery are:

• Infection
• Bleeding
• Malfunction
• Obstruction
• Overdrainage
• Underdrainage
• Shunt migration
• Abdominal complications

These complications may require revision or removal of the shunt, and they may worsen the symptoms of NPH or cause new symptoms. Therefore, the decision to undergo shunt surgery should be made carefully, after weighing the benefits and risks, and after consulting with a neurosurgeon who is experienced in treating NPH.

Normal pressure hydrocephalus treatment without shunt

Some patients with normal pressure hydrocephalus may not be suitable candidates for shunt surgery, either because of their age, medical condition, or preference. In these cases, the treatment options are limited, and they mainly aim to manage the symptoms and prevent complications. Some of the non-surgical treatments for NPH are:

Medications

There are no specific medications that can treat normal pressure hydrocephalus, but some medications may help with some of the symptoms, such as painkillers for headaches, anticholinergics for urinary incontinence, or antidepressants for mood disorders. However, some medications may also have side effects or interactions, and they should be used with caution and under medical supervision.

Physical therapy

Physical therapy has the potential to enhance an individual’s gait and balance. By engaging in this form of treatment, individuals can experience improvements in their ability to walk and maintain stability and mobility of the patients with NPH, and prevent falls and injuries. This treatment may involve exercises, stretching, massage, balance training, and assistive devices, such as walkers or canes, and by all means should be tailored to the individual needs and abilities of the patient, and supervised by a qualified physical therapist.

Occupational therapy

Occupational therapy can help improve the cognitive, behavioral, and functional abilities of the patients with normal pressure hydrocephalus, and enhance their daily living and quality of life. Occupational therapy may involve cognitive training, memory aids, environmental modifications, and adaptive strategies, such as using calendars, lists, or alarms. Occupational therapy should be customized to the individual goals and preferences of the patient, and guided by a certified occupational therapist.

Lifestyle changes

Lifestyle modifications can help reduce the risk factors and complications of normal pressure hydrocephalus, and promote the general health and well-being of the patients. Lifestyle modifications may include:

• Ensuring an adequate intake of fluids to maintain hydration levels, while being cautious not to consume excessive amounts that could strain the kidneys and bladder.
• Maintaining a well-rounded and nourishing diet that offers sufficient essential nutrients and fiber, while also steering clear of food items that have the potential to induce constipation, gas, or bloating.
• It is advisable to steer clear of alcohol, caffeine, nicotine, and any other substances that have the potential to impact brain function or the production and absorption of cerebrospinal fluid (CSF).
• Ensuring you receive an adequate amount of sleep and rest, as well as adhering to a consistent sleep routine.
• One crucial aspect of maintaining good mental health is effectively managing stress and anxiety, and being willing to seek professional assistance when necessary.
• Participating in a variety of social and leisurely endeavors that bring pleasure and mental stimulation, while also cultivating a optimistic mindset and perspective.

By adhering to the medical advice and instructions provided by healthcare professionals, and diligently following the recommended dosage and administration of prescribed medications. It is very important to promptly inform the doctor of any developments or deterioration in symptoms, as well as any indications of infection or possible malfunction of the shunt.

Normal pressure hydrocephalus dementia: how to live with it?

Living with NPH, or normal pressure hydrocephalus, can present various challenges, yet it is indeed feasible to effectively manage this condition and enhance one’s overall quality of life. In order to navigate the complexities associated with normal pressure hydrocephalus, there are several valuable tips and strategies that can be employed:

• It is essential to acquire knowledge about NPH, its origins, indications, identification, and therapy not only for yourself but also for your loved ones. By broadening your understanding of this condition, you will enhance your ability to effectively handle it and make well-informed choices.
• Seek support from others who understand what you are going through, such as your doctor, nurse, therapist, social worker, or support group. They can provide you with information, guidance, counseling, and emotional support.
• Communicate your needs and feelings to your family, friends, and caregivers. They can help you with your daily activities, provide you with comfort and companionship, and respect your dignity and privacy.
• Adapt your home and environment to make it safer and more comfortable for you. You may need to install handrails, ramps, grab bars, nonslip mats, or other devices to prevent falls and injuries. You may also need to rearrange your furniture, remove clutter, or use labels or signs to help you navigate and remember things.
• Plan ahead and organize your tasks and activities. You may need to use calendars, lists, alarms, or other reminders to help you keep track of your appointments, medications, bills, and other obligations. You may also need to prioritize your tasks, delegate some responsibilities, or ask for help when needed.
• Maintain your hobbies and interests, and explore new ones. You may need to modify some of your activities, such as reading, writing, gardening, or playing games, to suit your abilities and preferences. You may also need to try new activities, such as painting, knitting, or listening to music, to stimulate your brain and creativity.
• Be realistic and optimistic about your condition and your future. You may need to accept some limitations and changes in your life, but you should not give up on your goals and dreams. You should focus on your strengths and achievements, and celebrate your progress and improvements.

Conclusion

Normal pressure hydrocephalus is a condition that affects the brain and causes problems with walking, thinking, and bladder control. It is caused by the accumulation of excess CSF in the ventricles, which causes them to enlarge. It is often misdiagnosed as other neurological disorders, such as dementia, Alzheimer’s disease, Parkinson’s disease, or stroke. The main treatment for normal pressure hydrocephalus is surgery to place a shunt in the brain to drain the excess CSF. The surgery can potentially reverse the symptoms of NPH, and improve the quality of life and independence of the patients. However, the surgery is not without risks, and it does not work for everyone.

Some patients with normal pressure hydrocephalusmay not be suitable candidates for surgery, and may need to manage their symptoms and prevent complications with non-surgical treatments, such as medications, physical therapy, occupational therapy, and lifestyle modifications.

Living with NPH can be challenging, but it is possible to cope with the condition and improve the quality of life with education, support, communication, adaptation, planning, and optimism. We hope that our article will help you understand and deal with NPH and make your life better.