Medical Devices

Information for Clinicians about Magnetic Field Interference

The following strategies may help prevent unintended changes to magnetic externally adjustable CSF shunt valves:

Ensure Patients and Caregivers Understand the Risks

  • Provide patient education about precautions, including environmental sources of magnetic fields.
  • Inform patients of signs and symptoms that may be associated with valve setting changes.

Check Valve Settings Routinely

  • Verify that settings are correct. 
  • Examine patients to ensure that they are not experiencing over- or underdrainage of CSF.

Report Problems

As the primary users of CSF Shunts, clinicians play a critical role in conducting safety checks, assessing the performance of these devices, and reporting issues that impact their performance. Reporting problems with devices is one of the most effective ways to assist industry in resolving device issues and preventing future patient harm.

Additional data is needed to understand fully the possible relationship between magnetic externally adjustable CSF shunt valves and magnets found in the environment. However, it is reasonable to assume that a shunt valve that is manipulated by a hand-held magnetic tool may also be vulnerable to other external magnetic sources.

  • Report all details surrounding unintended valve-setting change events including, but not limited to:
    • Details of the resetting event, including the suspected distance of the shunt from the magnetic source
    • Identify the suspected magnetic source(s)
    • Severity of patient symptoms
    • Change in valve setting value from intended setting
    • Manufacturer and brand of magnetically adjustable shunt
    • Patient age, gender, underlying diagnosis for shunt (e.g. trauma, hydrocephalus)
    • Concomitant medical devices in region of shunt (i.e. cranial plate, cochlear implant
    • Device evaluation post-explant, if available
  • Be aware that HIPAA restrictions do not apply to reports submitted to the FDA.

Page Last Updated: 02/04/2018
Note: If you need help accessing information in different file formats, see Instructions for Downloading Viewers and Players.
Language Assistance Available: Español | 繁體中文 | Tiếng Việt | 한국어 | Tagalog | Русский | العربية | Kreyòl Ayisyen | Français | Polski | Português | Italiano | Deutsch | 日本語 | فارسی | English