Can common household devices alter the settings of programmable shunt valves?

Various household devices contain magnets or emit electromagnetic fields and it is hypothesised that the strength of these magnets may be enough to affect the settings on programmable cerebrospinal fluid shunt valves. The aim of this study is to identify changes to the valve settings of seven commonly used programmable valves, when they are near common household devices generating a magnetic field.

Several commonly encountered household devices were used, with and without rotational movement, with reference to seven commonly used programmable valves (the Codman Certas and Hakim, Sophysa SPV and SM8, Medtronic Strata II Regular and Small, and the Miethke M.Blue Plus). The valve settings were checked before and after the interference with the household device, by using either the manufacturers tool kit for reading the settings or x-rays.

We demonstrated that the only valve which was not affected by any of the household devices, regardless of the distance or rotational movement, was the Miethke M. Blue Plus. In addition, the programmable shunts were more likely to experience change to their settings with rotational movement as opposed to no movement, and the two devices most likely to induce this change were a smart watch and kids toy magnets.

Everyday household devices have the potential to affect the settings on programmable shunts, leading to concerns around the maintenance of shunt settings both in and out of hospital due to household and healthcare electromagnetic fields. Surgeons, and other healthcare professionals involved in the care of those with programmable CSF shunts, should be aware of the potential risks and utilise this information when making clinical decisions and advising patients.