The Effect of Constant Magnetic Fields on Programmable Shunts

Abstract

The valve pressure settings of the programmable shunt valves may be changed undesirably in the high magnetic field environments, and in many cases, these changes are not noticeable. Recent studies have shown that this effect increases in parallel with the increasing diversity of permanent magnet containing devices used in daily life. In this study, the effects of the non-ionizing magnetic field produced by devices such as smartphones and headphones on the programmable cerebral shunts were investigated. Codman Certas programmable valves, frequently preferred in the treatment of hydrocephalus, were used in this study. First, the minimum magnetic flux densities that could affect these valves when exposed to an external magnetic field have been determined. Then, the effect of the magnetic flux densities produced by two different earphones and a mobile phone on this valve was investigated. It has been observed that such external magnetic fields can cause undesirable pressure changes on the valves at close distances, and these results suggest that patients should be aware of this effect.