Normal pressure hydrocephalus is a condition where excess cerebrospinal fluid builds up in the brain, leading to walking difficulties, memory problems, and bladder control issues—yet with proper diagnosis and treatment, many of these symptoms can improve or even reverse.

Understanding Treatment Goals and Approaches

Normal pressure hydrocephalus, often called NPH, is one of the few brain conditions where symptoms like dementia and walking difficulties can actually be reversed with appropriate treatment. The main goal of treating this condition is to reduce the pressure that accumulated fluid places on the brain, thereby improving the patient’s ability to walk, think clearly, and control their bladder. Unlike many other age-related brain disorders, NPH responds well to intervention when caught early, offering hope for significant improvement in quality of life.^[1]

Treatment decisions depend heavily on several factors. The stage at which NPH is diagnosed plays a crucial role—the earlier the diagnosis, the better the potential outcome. Doctors also consider the severity of symptoms, the patient’s overall health, and the presence of other medical conditions that might complicate treatment. Because NPH primarily affects people over 65 years old, healthcare teams must carefully evaluate whether a patient is healthy enough to undergo surgical procedures.^[1]

There are established, proven treatments for NPH that medical societies around the world recognize and recommend. At the same time, researchers continue to explore new therapeutic approaches through clinical trials. These studies test innovative techniques that might offer advantages over traditional methods, such as less invasive procedures or better outcomes for specific patient groups. Some patients may have the opportunity to participate in these trials, potentially benefiting from cutting-edge treatments not yet widely available.^[10]

Standard Treatment Approaches

Ventriculoperitoneal Shunt Surgery

The primary and most widely used treatment for normal pressure hydrocephalus is a surgical procedure that involves implanting a device called a shunt. A shunt is a thin, flexible tube designed to drain excess cerebrospinal fluid (CSF)—the liquid that normally cushions and protects the brain—from the brain’s internal chambers (called ventricles) to another part of the body where it can be safely absorbed. This procedure is known as ventriculoperitoneal shunting, often abbreviated as VPS or VP shunt.^[1]

During this operation, a neurosurgeon makes a small opening in the skull and carefully inserts one end of the shunt tube into one of the brain’s ventricles. The tube then travels under the skin, running from the head down through the neck and chest to the abdomen (belly area). The excess fluid flows through this tube into the abdominal cavity, where the body’s natural processes absorb it into the bloodstream. This continuous drainage helps reduce the pressure on the brain and allows the ventricles to return to a more normal size.^[9]

Inside the shunt system, there is a small valve that can be felt as a lump under the skin on the scalp. This valve is crucial because it controls how fast the cerebrospinal fluid drains. If fluid drains too quickly, it can cause problems; if it drains too slowly, symptoms may persist. Many modern shunts use programmable valves that allow doctors to adjust the drainage rate without additional surgery. After the shunt is placed, doctors can fine-tune the valve settings externally using a special device, making it easier to find the optimal flow rate for each individual patient.^[14]

The surgery itself typically takes between one and two hours and is performed under general anesthesia, meaning the patient is completely asleep and feels nothing during the procedure. Most patients need to stay in the hospital for a few days after surgery to recover and to ensure the shunt is working properly. If stitches or staples were used to close the surgical wounds, they will need to be removed after several days, though some surgeons use dissolving stitches that don’t require removal.^[12]

Not all patients respond equally well to shunt surgery. When patients are carefully selected based on proper diagnostic testing, research shows that between 80% and 90% experience improvement in their symptoms. Walking problems are usually the symptoms most likely to improve following shunt surgery. Cognitive symptoms like memory problems and concentration difficulties may also get better, though sometimes to a lesser degree. Bladder control problems can improve as well, though these symptoms are generally less responsive to treatment than gait disturbances.^[14]

Potential Complications and Long-term Management

Like all surgical procedures, shunt surgery carries some risks. The most common complications include infection at the surgical site or along the shunt tubing, and mechanical problems with the shunt itself. A shunt can become blocked if tissue grows around it or if blood or protein clogs the tube. When a shunt stops working properly, symptoms of NPH typically return, and additional surgery may be needed to repair or replace the device.^[11]

Shunt infections usually occur within the first few weeks or months after surgery. Signs of infection may include fever, redness and swelling around the surgical wounds, headache, or a return of NPH symptoms. If an infection develops, doctors may need to remove the infected shunt, treat the infection with antibiotics, and then implant a new shunt once the infection is cleared.^[11]

Long-term follow-up care is essential for people living with a shunt. Patients need regular check-ups to ensure the device continues to function correctly. If symptoms return or new problems develop months or years after the initial surgery, this might indicate that the shunt needs adjustment or replacement. Because shunts are mechanical devices, they don’t last forever, and many patients will need additional procedures over their lifetime to maintain the shunt system.^[14]

Endoscopic Third Ventriculostomy

An alternative surgical approach called endoscopic third ventriculostomy, or ETV, may be suitable for some patients. Instead of implanting a shunt, the surgeon creates a small opening in the floor of one of the brain’s ventricles, allowing trapped cerebrospinal fluid to flow around a blockage and be absorbed naturally. This procedure uses an endoscope—a thin, flexible tube with a tiny camera and light at the end—which the surgeon inserts through a small hole in the skull.^[12]

ETV works best for patients whose hydrocephalus is caused by a specific type of blockage (obstructive hydrocephalus). Not everyone with NPH is a candidate for this procedure. However, when ETV is appropriate, it offers some advantages. Because no shunt device is left in the body, there’s no risk of shunt malfunction or the need for shunt adjustments over time. The risk of infection is generally lower with ETV compared to shunt surgery. The procedure takes about an hour, and many patients can go home within a few days.^[12]

The long-term results of ETV are similar to those of shunt surgery when the procedure is done on carefully selected patients. However, like shunts, the opening created during ETV can sometimes close up months or years later, causing symptoms to return. If this happens, a repeat procedure or shunt placement may be necessary.^[12]

Diagnostic Testing Before Surgery

Before recommending surgery, doctors perform several tests to confirm that a patient’s symptoms are truly caused by NPH and to predict how likely they are to benefit from treatment. These tests are crucial because surgery carries risks, and not everyone with enlarged brain ventricles will improve with a shunt.^[14]

One common test is called a tap test or large-volume lumbar puncture. During this procedure, a doctor inserts a thin needle into the lower back to remove a significant amount (typically 30 to 50 milliliters) of cerebrospinal fluid. Before the fluid is removed, the patient’s walking ability and cognitive function are carefully measured. Then, a few hours after the fluid removal, these same measurements are repeated. If the patient shows noticeable improvement in walking, balance, or thinking abilities after the tap test, this strongly suggests they will benefit from shunt surgery.^[14]

Another predictive test involves placing a temporary drainage catheter (tube) in the lower back that remains in place for several days. This is called external lumbar drainage. The catheter continuously drains small amounts of cerebrospinal fluid into a collection bag, simulating what a permanent shunt would do. Patients are closely monitored during this time, and their symptoms are assessed daily. Significant improvement during this drainage period indicates a high likelihood of success with permanent shunt surgery.^[14]

A third type of test measures CSF outflow resistance through an infusion test. During this procedure, fluid is slowly introduced into the cerebrospinal fluid space while pressure is monitored. High resistance to fluid flow suggests that the body is having difficulty absorbing cerebrospinal fluid normally, which supports the diagnosis of NPH and suggests that shunt surgery will be helpful.^[14]

Innovative Treatments in Clinical Trials

Minimally Invasive eShunt System

One of the most promising developments in NPH treatment being tested in clinical trials is a minimally invasive device called the eShunt System. This innovative approach represents a significant departure from traditional shunt surgery and could potentially transform how doctors treat this condition.^[10]

Unlike conventional shunt surgery, which requires drilling holes in the skull and threading a long tube through the body to the abdomen, the eShunt is implanted entirely through blood vessels. Surgeons access the system through the femoral vein in the groin—the same blood vessel often used for heart catheterization procedures. Using specialized imaging equipment, they guide the eShunt device through the blood vessels up to the area where cerebrospinal fluid accumulates at the base of the skull. The device creates a connection between the CSF space and a vein in the neck, allowing excess fluid to drain directly into the bloodstream where it is naturally reabsorbed.^[10]

The advantages of this approach are considerable. There is no need to shave the patient’s head, no hole drilled in the skull, and no long tube running through the body. The entire procedure is done through a small needle puncture in the groin, similar to what patients experience during many heart procedures. Because it’s less invasive, the risk of infection is potentially lower than with traditional shunt surgery. Recovery time may be shorter, and the procedure may be safer for patients who have other health conditions.^[10]

The eShunt System is currently being evaluated in a large Phase III clinical trial called STRIDE. This is a randomized, controlled study, which means that participants are assigned by chance to receive either the new eShunt device or a standard traditional shunt. Researchers will compare outcomes between the two groups to determine whether the eShunt is as effective as traditional surgery and whether it offers advantages in terms of safety and complications. Yale Medicine neurosurgeon Dr. Charles Matouk serves as the global co-principal investigator for this study, and Yale has been the highest-enrolling center in the United States, with significant experience using the eShunt device.^[10]

Preliminary results from earlier pilot studies have been very encouraging. These initial studies suggested that the eShunt device is safe and that the implantation procedure is feasible. Patients who received the device showed improvements in their NPH symptoms, and the complication rates appeared favorable. However, these were small early studies, and the Phase III trial will provide more definitive evidence about how the eShunt compares to standard treatment.^[10]

To participate in the STRIDE trial, patients must meet rigorous criteria based on both their clinical symptoms and brain imaging findings. Not everyone with NPH qualifies for the study. Patients interested in this option should discuss with their healthcare providers whether they might be eligible and whether a center participating in the trial is accessible to them. The trial is being conducted at multiple sites, with Yale Medicine having the most extensive experience in the United States.^[10]

Future Applications of Minimally Invasive Technology

Researchers believe that if the eShunt proves successful for treating normal pressure hydrocephalus, this minimally invasive technology could potentially be adapted for other types of hydrocephalus as well. There is significant interest in exploring whether similar approaches might work for hydrocephalus in children (pediatric hydrocephalus), for hydrocephalus that develops after brain bleeding (hemorrhage-related hydrocephalus), and for related conditions like idiopathic intracranial hypertension—a disorder where pressure inside the skull is too high even without excess fluid accumulation.^[10]

The development of less invasive treatment options reflects a broader trend in medicine toward procedures that minimize surgical trauma while maintaining effectiveness. For elderly patients with NPH, who often have multiple other health conditions that increase surgical risks, minimally invasive approaches could be particularly beneficial. Even small reductions in surgical risk can be meaningful for this vulnerable population.^[10]

Most common treatment methods

• Ventriculoperitoneal Shunt Surgery
  • Surgical implantation of a thin tube that drains excess cerebrospinal fluid from the brain’s ventricles to the abdomen
  • Contains a programmable valve that allows doctors to adjust drainage rate without additional surgery
  • Surgery performed under general anesthesia, typically taking one to two hours
  • Hospital stay of a few days required for recovery and monitoring
  • Success rate of 80-90% when patients are properly selected through diagnostic testing
  • Walking problems most likely to improve; cognitive and bladder symptoms may also improve
  • Long-term follow-up necessary to monitor shunt function
  • Potential complications include infection and mechanical malfunction requiring repair or replacement
• Endoscopic Third Ventriculostomy (ETV)
  • Minimally invasive procedure that creates a small opening in the brain’s ventricle floor
  • Allows trapped cerebrospinal fluid to flow around blockages and be absorbed naturally
  • Uses an endoscope (thin tube with camera) inserted through a small skull opening
  • Most suitable for patients with obstructive hydrocephalus; not appropriate for all NPH cases
  • No permanent device left in body, eliminating risk of shunt malfunction
  • Lower infection risk compared to traditional shunt surgery
  • Procedure takes approximately one hour
  • Opening may close over time, potentially requiring repeat procedure or shunt placement
• Diagnostic Procedures
  • Tap test (large-volume lumbar puncture) to remove cerebrospinal fluid and assess symptom improvement
  • External lumbar drainage with temporary catheter for several days to simulate permanent shunt effects
  • CSF outflow resistance testing through infusion studies to measure fluid absorption capacity
  • Brain imaging with MRI or CT scans to visualize enlarged ventricles
  • Neurological examinations and gait testing to document baseline symptoms and treatment response
• Innovative Clinical Trial Treatments
  • eShunt System: minimally invasive device implanted through blood vessels via groin access
  • Creates connection between cerebrospinal fluid space and neck vein for drainage into bloodstream
  • No skull drilling or head shaving required; entire procedure through small groin puncture
  • Currently evaluated in Phase III STRIDE clinical trial comparing with traditional shunt
  • Pilot studies showed encouraging safety and feasibility results
  • Available at select clinical trial sites with rigorous eligibility criteria
  • Potential future applications for pediatric and hemorrhage-related hydrocephalus