Have you had a shunt fitted in your head, possibly if you have hydrocephalus, a build-up of fluid in the brain?
If so, you need to let us know when you come for a hearing test with one of our audiologists.
The pressure caused by excess fluid surrounding the brain is usually treated with a surgically implanted device that drains this fluid. Some of these devices are programmable and they are known as PVP shunts.
Changes in pressure
They have a magnetically adjustable valve placed under the skin, often on or near the mastoid bone, so that they can be adjusted by an external control magnet if needed.
However, the magnetic valve in some PVP shunts can be susceptible to other magnetic fields and may be readjusted by relatively weak fields, leading to a potentially dangerous change in pressure.
Please tell your audiologist
Some audiology equipment and hearing aid devices, including cochlear implants, some earphones, bone conductors and other equipment generate a magnetic field and may risk inadvertently adjusting the PVP shunt.
If you have one of these devices, then please let your audiologist know when booking your appointment.