When Gary Chaffee was in his early thirties, he had a visual field test that prompted an eye doctor to order a CT scan. The images revealed enlarged brain ventricles, the network of interconnected, fluid-filled cavities that produce and transport the cerebrospinal fluid (CSF) that cushions the brain, removes waste, and helps maintain a stable environment for the central nervous system.

Based on that result, a neurologist diagnosed Chaffee with hydrocephalus, a chronic neurologic condition marked by an abnormal accumulation of CSF in brain ventricles that can lead to a wide range of symptoms and potential brain damage. “My hydrocephalus, which was found by accident, went on the back burner while I charged ahead with my work and family life,” says Chaffee, a former medical technology executive who lives in Flower Mound, TX.

Then in 2002, when Chaffee was 55, he began having debilitating symptoms he couldn't ignore. “I would have to make six trips to the bathroom during a two-hour business meeting, my feet started to feel like they were stuck to the ground when I tried to walk, and I would forget what I was supposed to talk about in meetings if I didn't have the floor immediately,” he says. His doctors provided a more specific diagnosis of normal pressure hydrocephalus (NPH), which is more common in older people. A year later, Chaffee retired. He subsequently had eight brain surgeries, initially to place a shunt to relieve the fluid pressure, and seven more to replace failed shunts. “I went from having a great career to total disability,” Chaffee says. Now 77, he leads a very different but equally fulfilling and productive life.

Sydney Treat was diagnosed with congenital hydrocephalus soon after being born prematurely. She underwent brain surgery as an infant and had three more surgeries when she was 9. Now 25 and a young professional in Washington, D.C., she has just one lingering symptom, strabismus, an eye misalignment commonly associated with congenital hydrocephalus. While some children with the condition struggle with developmental delays, seizures, learning disabilities, and a host of other challenges, Treat says the condition does not dominate her life. However, she says, “I know hydrocephalus can come in different forms for others.”

A Highly Variable Disorder

Each year in the United States, one in every 500 babies is born with hydrocephalus, and another 6,000 children develop it before they turn 2. Of the more than 1 million Americans with the condition, three-quarters are adults. The presence and severity of symptoms can vary widely based on age and how quickly the condition is recognized and treated, according to the National Institute of Neurological Disorders and Stroke.

“We don't know why patients get symptoms or why they get better,” says Michael A. Williams, MD, FAAN, professor of neurology and neurologic surgery at the University of Washington School of Medicine in Seattle. “Researchers are chasing answers, including looking at how CSF moves through the brain.”

Even categorizing the many types of hydrocephalus is complex. “Hydrocephalus is an umbrella term because there are so many reasons it can occur,” says Alberto Espay, MD, FAAN, professor of neurology at the University of Cincinnati in Ohio.

Congenital hydrocephalus can be caused by premature birth, spina bifida, or genetic disorders like Dandy-Walker syndrome, a brain malformation at birth in which the part that connects the two hemispheres of the cerebellum doesn't develop fully, and the fourth ventricle and the area behind the cerebellum fill with CSF, says Dr. Williams.

Acquired hydrocephalus, which develops after birth, can be caused by head trauma, brain tumors, cysts, brain bleeds, or infections of the central nervous system, according to the Hydrocephalus Association.

Hydrocephalus also can be classified as obstructive or communicating. Obstructive hydrocephalus results from a physical blockage like a tumor, aqueductal stenosis (a narrowing of a small duct that connects the third and fourth vertebrae and blocks CSF), or Dandy-Walker malformation. Communicating hydrocephalus, such as NPH, involves problems with the flow of CSF over the surface of the brain to areas where CSF is absorbed, says Dr. Williams.

In many instances, hydrocephalus is considered idiopathic, meaning there is no obvious cause. It also may be part of a complex of symptoms in an array of genetic disorders, says Bruce H. Cohen, MD, FAAN, director of the NeuroDevelopmental Science Center at the Children's Hospital Medical Center of Akron in Ohio.

Getting a Correct Diagnosis

When symptoms will appear and how severe they will be is difficult to predict, says Dr. Williams. For instance, it's not clear why Chaffee didn't experience symptoms until 20 years after he was diagnosed, or why they occurred when they did. “We don't know why symptoms can be delayed, or why some people have certain symptoms and others don't,” says Dr. Williams. “We have to go back to basics and look at patients’ brain scans, listen to their stories, and perform comprehensive neurologic examinations to see if there's an association with hydrocephalus.”

Because of its variability, and because symptoms such as impaired walking and balance, urinary urgency or incontinence, and cognitive impairment can be caused by other conditions, NPH is often misdiagnosed. For example, it can be mistaken for Alzheimer's disease, which also causes brain tissue to shrink, leading to an increase in CSF volume. For a time prior to his NPH diagnosis, Chaffee thought he might have Alzheimer's.

As a result, Dr. Williams says, it's imperative to ascertain whether a patient's symptoms are related to hydrocephalus before providing treatment. “It's common to see a brain scan with big ventricles but no symptoms, or symptoms from other conditions,” says Dr. Williams. “We want to be sure we're addressing the right thing.”

For patients suspected of having NPH, a first step is a lumbar puncture to remove CSF. “If the patient improves, you can be 85 to 90 percent certain that they have hydrocephalus and a shunt will help.” If there is no improvement after a spinal tap, Dr. Williams says, the patient likely does not have hydrocephalus.

A relatively new test that is becoming more common is a volumetric assessment through MRI, says Dr. Espay. “If we suspect that patients have NPH, we can test to see whether the brains have a normal volume of CSF and whether ventricular volume is normal.” Such tests can help clinicians differentiate between NPH, if the volume is too high, and other conditions such as Alzheimer's disease, Dr. Espay says.

Treatment

In almost all cases of hydrocephalus, excess CSF must be removed or diverted in order to reduce pressure on the brain and prevent brain damage. This is usually achieved by a three-part shunt system: a thin catheter tube that's inserted into the brain's ventricles or the CSF space of the lumbar spine, a valve that regulates the flow of CSF through the shunt system, and a distal catheter that tunnels under the skin to the area where the CSF will be drained and absorbed, such as the abdominal cavity, large veins leading to the heart, or the pleural cavity.

Shunts are considered safe and effective, but complications include obstruction in adults and infection in children, says Dr. Williams. “The valve is adjustable, and the settings can be adjusted magnetically. This simplicity is both the beauty and the bane of the shunt, because it can get clogged.” Clogs can occur for many reasons, including infection-related protein deposits in CSF, a kink in tubing, or improper placement of the catheter. Chaffee knows this firsthand, as he's on his eighth shunt. “I'm one of those people who tends to get my shunt clogged, so I've had a new one every three years.”

Still, he says, the treatment saved his life. In 2005, he was declining rapidly; he believes the shunt kept him from moving to a nursing home. While he was apprehensive about the surgery at first, he had little pain and no headache afterward and felt much clearer almost immediately. “I got my life back pretty quickly. I still have some deficits, but with the shunt I lead a very active, good life. I tell newly diagnosed people that they'll still be able to live fully. I was able to go back to traveling and volunteering, and there are some days I work as hard now as I did before hydrocephalus. A shunt is not perfect, but it keeps me going, and I have no regrets.”

Treat had a shunt inserted as an infant and was 9 before she needed a new one. She was visiting California for a wedding with her family when the initial shunt failed, and she recalls feeling miserable before being taken to the hospital for an emergency shunt revision. “I was dizzy and vomiting and wailing with pain.”

Unfortunately, that shunt also failed, and Treat had three shunt revisions in 2008, although she hasn't needed another one since. She still has anxiety around needles and other hospital-related triggers, but she gives little thought to her shunt unless someone hears her story or takes note of it in conversation. “It's part of me, and sometimes I wonder why people don't ask more questions,” Treat says. “I don't worry about it too much, but my mind can get racing when I have my annual visit to the neurologist.”

With so many revisions under his belt, Chaffee says, he can identify when his shunt is beginning to fail. “If I feel like I am walking more wildly and out of balance, I'll start monitoring. Then I'll watch for urinary increase and cognitive troubles and not being able to focus in conversation. When I hear from my wife that I need to get my head examined, then I know it's time.” Because he's bald, Chaffee's shunt is visible. “It gives me an opportunity to talk about NPH and show newly diagnosed people that it's not a big deal.”

Improving the efficacy of shunts and ensuring that surgery is done properly are important research goals, says Dr. Williams. “In children, every time there is a shunt infection, the odds of another infection are three to four times higher, if not more.”

Shunts are most effective for people who have nonobstructive hydrocephalus, such as NPH, says Dr. Espay. People with hydrocephalus caused by congenital malformations, tumors, cysts, or other structural abnormalities may benefit from endoscopic third ventriculostomy, a procedure in which a tube with a camera is used to puncture the membrane of the third ventricle, opening a natural pathway that allows CSF to flow around a blockage.

Continuous Care

When children with hydrocephalus transition into adulthood, or if adult patients move across the country, it can be difficult to find neurosurgeons to care for them since they've already had brain surgeries performed by other doctors.

The problem is common and troubling, says Dr. Williams. “Imagine if a cardiologist wouldn't or couldn't help a patient who'd had a pacemaker put in by another doctor. Part of the challenge is that many neurologists haven't been trained to help patients with shunts. All residents should be educated about shunts. It's a unique learning opportunity, if only to demystify that care.”

Another problem is a lack of understanding about why people develop NPH and why they get better, says Dr. Williams. “We don't yet understand the pathophysiological mechanisms of symptom development and recovery. Thus, the existence of NPH has been called into question.”

Quality research over the last 20-plus years has increased understanding of the condition, he says. For example, a recent Cochrane review of four small, randomized trials of shunt surgery for NPH concluded that it improves walking speed and decreases disability in the first six months. Dr. Williams is hopeful that studies with more participants will add to the understanding.

Stress Management

The anxiety Treat still experiences on occasion is not uncommon in people with hydrocephalus, says Dr. Williams. “It's a huge stressor on kids as well as their families and can cause psychological and psychosocial issues.”

For Treat, talking things through with her parents helps. “I have such a good life and don't see myself as someone who is struggling or disadvantaged. It's appropriate to recognize the hardship of it, but ‘poor Sydney’ gets under my skin,” she says.

Chaffee says a routine of projects, fun, and exercise keeps him positive. Since his last shunt surgery, in October 2023, he's worked up to five-mile walks. “I work on a project for a few hours and cut myself some slack on trying to overachieve and multitask. Then I'll exercise and maybe go back to the project or incorporate some fun, like playing a video game recommended by my grandson.”

Like Treat, Chaffee doesn't allow too much self-pity. “I give myself 15 minutes per day to say ‘Woe is me,’ and then I go about my business.”

Hydrocephalus Resources

• Hydrocephalus Association
• National Organization for Rare Disorders
• Normal Pressure Hydrocephalus Support Group