A new procedure may change the way communicating hydrocephalus is treated
CereVasc is a medical device company currently developing the eShunt® System as a potential new treatment option for patients with communicating hydrocephalus. The current standard of care requires an invasive surgical technique that has a risk of severe complications. The eShunt® System, still in the clinical trial phase, offers a minimally invasive option.
Dan Levangie, president and CEO of CereVasc, spoke about the eShunt® System and gave an update on the path to potential FDA approval.
Q: Can you tell us about CereVasc?
Daniel Levangie: CereVasc is an early-stage medical device company focused on improving the treatment of patients with communicating hydrocephalus through a unique transvascular approach. The system is based on an invention and discoveries from the neurosurgery team at Tufts Medical Center in Boston.
Q: Can you give some background on communicating hydrocephalus and some of its causes?
Daniel Levangie: In general, hydrocephalus is a disorder in the production and flow of cerebral spinal fluid (CSF). In patients with communicating hydrocephalus, there is no physical obstruction to the flow of CSF, but patients cannot reabsorb excess CSF that is produced deep in the ventricles of the brain.
Normally, individuals produce roughly 400 mL of CSF each day. That fluid surrounds the brain and the spinal column, providing nutrients and cushioning the tissue. We can only accommodate roughly half of the volume produced. There is a constant reabsorption of CSF that occurs through naturally occurring structures in the vasculature of the brain called arachnoid granulations. Essentially, we produce twice as much CSF as we can accommodate. There is reabsorption of about half of that to maintain normal intracranial pressure.
Patients with communicating hydrocephalus have a dysfunction of that reabsorption and thus have increasing intracranial pressure that can be exhibited by the development of headache, nausea, and vomiting; it can also induce a coma, and eventually, patients can die if the disorder goes untreated.
Q: How is communicating hydrocephalus historically treated? What are some of the challenges and unmet needs that persist?
Daniel Levangie: For the last approximately 60 years, the condition has been treated with an open surgical procedure. In the United States, the most common configuration is called a ventricular peritoneal shunt procedure. Essentially, it’s a series of catheters that connects the ventricle in the brain to another body cavity, typically the peritoneum, that allows the excess CSF to flow under pressure from the ventricle of the brain down through a set of catheters that are placed during the surgery. The CSF is then reabsorbed, in this case, into the peritoneum.
The procedure is an open surgical procedure that requires a burr hole in the skull and passage of a catheter through brain tissue to reach the ventricle. That catheter is then typically attached to a valve that is placed subcutaneously behind the ear. Then a long subcutaneous tunneling procedure takes place that allows the passage of a long catheter down across the chest and abdomen where it terminates in an incision in the abdomen to allow the end of that catheter to reside in the peritoneum.
Basically, it’s a long catheter system that allows passage of CSF from the ventricle down through the body, which is reabsorbed into the peritoneum. The complication rate of that procedure is very high. Patients experience postoperative infection, and the catheters can become clogged and twisted, which prevents the flow of CSF.
In elderly patients who commonly have communicating hydrocephalus, the length of the catheter causes too much flow of CSF in some cases. They have symptoms related to over-drainage and headaches when they sit up. In extreme cases, they can experience subdural hematoma because of excess CSF flow. It is a complicated 60-year-old open surgical procedure with a very high rate of complication.
Q: CereVasc is developing the eShunt® System, which is currently in clinical trial development. Can you talk about that system? How does it work, and how does it compare to the current standard of care?
Daniel Levangie: The original concept and development came from the neurosurgery team at Tufts Medical Center in Boston. The original idea came from the chairman of neurosurgery, Carl Heilman, MD. Dr. Heilman had done hundreds of shunt procedures, and he recognized that, in many areas of surgery, open surgical procedures were being improved by converting to minimally invasive endovascular procedures. One example most people are familiar with is in the cardiac space where 20 or 25 years ago, if you had a heart valve that failed, you would typically undergo open heart surgery, which would be required to replace that valve. Today, almost all of those procedures are done in a minimally invasive way using catheter-based techniques, which allow the placement of a replacement valve without opening your chest.
Dr. Heilman’s concept was to develop an endovascular approach in which we would be able to treat patients with hydrocephalus without open surgery. The concept started there, and we’ve capitalized on the developments in imaging technology, both MRI and CT imaging, that allow us to navigate from a femoral venous access point. We enter the femoral vein in the groin, and then we navigate a catheter up to the base of the brain. We then place a very tiny catheter device that connects the subarachnoid space where the CSF resides to a venous vessel from the brain. We allow CSF to flow as it does naturally. We’ve basically developed an implant that mimics the function of the naturally occurring arachnoid granulation that we depend on to allow CSF to flow under pressure and be reabsorbed back into the venous system.
The eShunt® is a very tiny permanent implant. We’ve placed the device in more than 50 patients, and we’ve had really terrific efficacy results, with effectiveness in reducing intracranial pressure and the symptoms of hydrocephalus. We’ve done that with very few complications. We’ve had no infection reported, nor any instances of over-drainage symptoms. We’ve had no complications related to cerebral hemorrhage when the catheter is placed in the traditional fashion. We’re very excited by the initial clinical results from our pilot studies.
Q: If approved, how do you foresee the eShunt® System changing the treatment landscape for communicating hydrocephalus?
Daniel Levangie: In at least 2 ways. The first is in newly diagnosed patients; I think most patients, given the choice, would opt for a minimally invasive treatment for their hydrocephalus compared to an open surgery that requires a burr hole in the skull and a pretty aggressive surgical technique to place catheters. I think in the newly diagnosed patient, that choice would certainly drive utilization of the eShunt® system.
The other way this technology can transform the market is that many elderly patients have communicating hydrocephalus who do not undergo treatment because they’re frail. They may be on anticoagulants for other conditions or have preexisting comorbid conditions that make them poor surgical candidates. In one of our pilot studies, we’re treating patients older than 65 years, many of whom are frail and are on anticoagulants. We’re able to treat those patients because this is not open surgery. Our therapy requires minimally invasive catheter-based techniques.
I think the newly diagnosed patient is likely to opt for a minimally invasive approach. Secondly, I think we can increase pretty dramatically the number of elderly patients who undergo treatment for this disorder who today opt not to be treated and continue to decline and have a very high rate of mortality. The 5-year mortality rate in these patients is very high when they’re not treated.
Q: What is the status of the clinical trial assessing this system?
Daniel Levangie: We are about to start the FDA-approved pivotal clinical trial that we hope to conduct during the next 12 to 18 months and file for approval with the FDA. We hope to be able to bring our eShunt® product to market sometime toward the end of 2026. In the interim, we continue to have requests from the neurosurgery community for either compassionate or emergency use in some patients who require treatment but have complications or contraindications to the current open surgery.
For example, we had an emergency-use treatment of a young woman who had a ruptured aneurysm and developed hydrocephalus as a result of that. She had a large blood clot in her leg, so she was being actively treated with anticoagulation, and she developed hydrocephalus. In that patient, treatment with the conventional approach is contraindicated. We were able to treat that patient effectively, reduce the complications, and reduce the impact of hydrocephalus on her condition. I think there are many indications for a device like this that will be really exciting and improve the care of patients once we come to market.
Q: What has been the feedback from the neurosurgery community?
Daniel Levangie: In general, the feedback from neurosurgeons is that they all perform the conventional shunt procedure, certainly during their training and thereafter. It’s not a procedure that they typically enjoy performing. It is an aggressive surgery. The complication rate is very high, and, as a result, the follow-up management can be complicated. In general, they are anxiously awaiting new technologies, and I think they see our device as a breakthrough that will allow them to treat many more patients and avoid the complications they currently experience with conventional treatment.
Learn more at https://cerevasc.com/.
