To the Editor: In about 80 percent of all cases of hydrocephalus,the accumulation of cerebrospinal fluid is treated with shuntvalves.1 Over the past 30 years, magnetically adjustable valveshave become widely accepted and routinely implanted devices.In central and northern Europe, adjustable valves are routinelyimplanted for about 40 percent of all shunts (in Sweden, 37percent of those used are made by Codman-Medos, 3 percent bySophysa).2 Despite the widespread use of these valves, onlya few studies regarding possible interactions with clinicalmagnetic resonance imaging (MRI) have been published. As high-fieldMRI is increasingly available and . . . [Full Text of this Article]