FDA Letter to Health Care Providers – Potential for Magnetic Field Interference in Patients with Cerebrospinal Fluid Shunt Systems and Implanted Hearing Devices
The Food and Drug Administration (FDA) wants to make audiologists and other health-care providers aware of potential complications in patients implanted with both cerebrospinal fluid (CSF) shunt systems and hearing implants that contain magnets, such as cochlear implants, bone-conduction hearing devices, or middle-ear hearing devices.
Specifically, the FDA warns that
"Magnetic interactions between these devices may occur when implanted in close proximity to each other. These interactions may lead to unintended changes to the programmable CSF shunt valve settings. If magnetic interactions inadvertently change the programmable CSF shunt valve settings, then over- or under-drainage of CSF may occur. Patients may experience symptoms such as altered mental status, headaches, lethargy, irritability, vomiting, changes in vision, and difficulty walking. If left untreated, symptoms could progress to include loss of consciousness, seizures, hemorrhage, or even death."
Education about potential device interactions and risks should be provided to caregivers and patients. Any adverse events should be reported to the FDA through MedWatch, the FDA Safety Information and Adverse Event Reporting program.
Readers are advised to consult the full text of the FDA alert for additional details, including recommended protocols for surgical placement of devices to reduce the risk of magnetic field interference.