Summary:
UCLA researchers in the David Geffen School of Medicine and Department of Neurosurgery have created a novel ventriculoperitoneal shunt failure detection system that can alert patients and healthcare providers to prevent life-threatening emergencies.
Background:
Each year, an estimated 30,000 ventriculoperitoneal (VP) shunts are surgically implanted in the United States to drain excess cerebrospinal fluid (CSF) from patients suffering from hydrocephalus and divert it to the abdomen. A significant proportion of these shunts face failure within the first two years, due to causes such as shunt obstruction, valve malfunction, or catheter fractures. These issues become apparent as early as the first year, with a substantial 30-40% of shunts experiencing failure, and a staggering 50% of these failing within two years of implantation. The commonality among all these failing cases is the interruption of CSF flow through the shunt.
There is currently no FDA-approved, fully implantable VP shunt failure detection system capable of autonomously alerting patients and physicians to deteriorating shunt performance. While several devices have been developed for measuring CSF flow rate within VP shunts, their practical utility is hindered by various limitations, including over-the-skin operation, power-expensive operation which precludes battery-powered implantation, intermittent functionality, insufficient sensitivity for monitoring slow CSF flow, and disruption of CSF flow dynamics. Consequently, the need for an advanced warning system is increasingly evident, one that can alert both patients and medical care personnel to declining shunt function and impending VP shunt failure before the onset of symptoms, thus mitigating life-threatening emergency scenarios.
Innovation:
Professor Geoffrey Colby, David Zarrin, and their team have developed an innovative VP shunt failure detection system that can be seamlessly integrated into existing VP shunt systems during placement. This technology not only proactively alerts patients but also keeps medical care personnel informed about diminishing shunt function and the impending risk of VP shunt failure, significantly reducing the potential for life-threatening emergencies. At the core of this advancement is a highly sensitive flow sensor capable of measuring CSF flow with exceptional precision. It can detect flows as low as 0.01 mL/minute through a CSF shunt valve assembly and measure rates up to at least 0.3 mL/minute, covering the full range of physiologic CSF generation rate.
The system consumes minimal power, making it an ideal candidate for use in an implantable and battery-powered VP shunt failure detection system. Additionally, the sensor's compact dimensions and flexibility allow for straightforward implantation with a new shunt system or to upgrade an existing shunt system, with minimal added bulk. This design also prioritizes patient comfort and compliance. Ultimately, this innovative technology not only promises to enhance awareness of shunt health but is also of paramount importance for the well-being of the thousands of patients in the United States whose health relies on the continued functionality of their ventricular shunting system.
Potential Applications:
- VP shunt health/function detection system
- Intracranial Pressure (ICP) Monitoring
- Traumatic Brain Injury (TBI) Management
- Pressure sensing scenarios that require compatible and delicate designs
Advantages:
- Sensitive to low CSF flow velocities
- Functional over the range of relevant CSF flow velocities
- Low power use for existing implantable system
- Robust sensing mechanism
- Compact and flexible
- Compatible with the existing VP shunt systems
Development to Date:
First successful demonstration of the invention completed.
Reference:
UCLA Case No. 2023-057
Lead Inventor:
Prof. Geoffrey P. Colby and Mr. David A. Zarrin.