P 68 Unintentional maladjustment of a shunt valve due to electromagnetic door locks – A case report

Abstract

Normal-pressure hydrocephalus is caused by dilatation of the internal cerebrospinal fluid spaces at normal intracranial pressure. The resulting progressive accumulation of CSF in the brain space can cause permanent damage and, if left untreated, complete loss of brain tissue [2, 4]. The standard treatment for hydrocephalus in children and adults is the implantation of a ventriculo-peritoneal shunt (VP shunt). Most of the currently used shunt systems have a valve to control pressure and drain CSF if necessary [4]. In recent years, malfunction of programmable VP shunts has been reported in patients exposed to strong electromagnetic fields, such as those generated during magnetic resonance imaging (MRI) [1, 3]. However, little is known about the effects of weak magnetic fields on VP shunts. We present the case of a 53 -year-old forensic psychiatric patient in whom the pressure setting of an implanted Codman-Hakim programmable shunt valve changed during passage through various ward doors, leading to the onset of psychiatric symptoms. During the inpatient stay, the valve's pressure setting changed at least six times randomly despite frequent reprogramming and monitoring. References 1 Akbar M, Aschoff A, Georgi JC, Nennig E, Heiland S, Abel R, Stippich C (2010) Adjustable Cerebrospinal Fluid Shunt Valves in 3.0-Tesla MRI: a Phantom Study using Explanted Devices. Rofo 182(7):594-602 2 Kahle KT, Kulkarni AV, Limbrick DD, Warf BC (2016) Hydrocephalus in children. Lancet 387(10020):788–799 3 Mirzayan MJ, Klinge PM, Samii M, Goetz F, Krauss JK (2012) MRI safety of a programmable shunt assistant at 3 and 7 Tesla. Br J Neurosurg 26(3):397-400 4 Portillo Medina SA, Franco JVA, Ciapponi A, Garotte V, Vietto V (2017) Ventriculo-peritoneal shunting devices for hydrocephalus. Cochrane Database Syst Rev. 2017(7): CD012726 Figure 1. Scetch of a Codman-Hakim shunt valve. Figure 2. Image of a Codman-Hakim VP shunt before and after passing a door.