Shunt Flowmeter
Sensor to measure cerebrospinal fluid (CSF) flow in a ventriculoperitoneal (V-P) shunt
The hydrocephalus shunt flowmeter is the first fully implantable device that can accurately measure the draining rate of cerebrospinal fluid
Background
Hydrocephalus is a life-threatening disease affecting two in every thousand children born. It causes fluid to build up inside the skull and therefore requires cerebrospinal fluid drainage via an implanted shunt that drains. However, shunt failure is common, with most shunts requiring a revision after about one year. This is frequently due to blockages from ingrowing tissue. Whenever a shunt failure is suspected, diagnostic tests called a ‘shunt series’ are needed to ensure continual drainage. Current shunt series evaluations use cranial imaging techniques, largely MRI or CT scans. With the average person having at least 9 shunt series in their life, and every single shunt series administering over 2 years of background radiation, the shunt series themselves are leading to precarious consequences, most frequently brain cancer. Several thousands of dollars are spent on shunt series by each patient when in fact most have little need for a shunt series – 83% of shunt series performed prove no intervention is necessary, with a further 4.3% of shunt series creating ‘false’ positives, where no intervention should have been done.
Our Solution
The Vivonics Shunt Flowmeter is a small implant that is placed in line with the existing shunt catheter under the skin. Together with an external readout unit (figure below), it provides an accurate and quantifiable measure of the volumetric flow of CSF within the shunt. The Shunt Flowmeter enables point-of-care, remote, and continuous monitoring at the clinician’s discretion. It enables the clinician to see changes in CSF on a real time basis and anticipate shunt failure issues without exposing the patient to high levels of harmful radiation.
Disclaimer: The project described was supported by Award Number R43NS056628 from the National Institute Of Neurological Disorders And Stroke. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute Of Neurological Disorders And Stroke or the National Institutes of Health.
(Award R43NS056628 is titled: Microfabricated Implantable Flowmeter for CSF Shunts)
Product under development, not yet FDA approved