title: Electromagnetic environmental influences on implanted deep brain stimulators.
abstract: Objective.  The objective of this study was to report our observations on the external electromagnetic field influences on deep brain stimulation (DBS) in our patient population and how these influences affected our patients' lives and other healthcare-related conditions. Materials and Methods.  We have retrospectively analyzed data concerning the effects of external electromagnetic fields on 172 of our patients implanted with DBS. Results.  Identifiable electromagnetic sources turned the implantable pulse generator (IPG) off in 20 patients. In two patients, these episodes necessitated replacement of the Itrel II IPG (Medtronic Inc., Minneapolis, MN, USA) with the magnetically shielded Kinetra IPG (Medtronic Inc.). Six patients received cardiac pacemakers, leading, in two patients, to interference between the systems. Our experience concerning magnetic resonance imaging, electrocardiogram (ECG), heart defibrillation, electro-cautery, and other sources of electromagnetic interference also is described. Conclusions.  External electromagnetic interference may, in rare cases, constitute a severe threat to the well-being of the patient implanted with a DBS system. Also, malfunction of a DBS system may constitute a medical emergency. Nevertheless, in spite of these external electromagnetic influences, we consider DBS to be a safe method, provided safety protocols are followed, and provided that provider awareness about potential hazards is present.
authors.affiliation: Department of Neurosurgery, University Hospital, Umeå, Sweden;              Parkinson, Memory and Movement Disorders Center, Notre Dame des Secours Hospital, Byblos-Lebanon;              School of Medicine, Université Saint Esprit, Kaslik, Lebanon.
authors.forename: Patric
authors.initials: P
authors.lastname: Blomstedt
authors.forename: Mazen
authors.initials: M
authors.lastname: Jabre
authors.forename: Boulos-Paul
authors.initials: BP
authors.lastname: Bejjani
authors.forename: Lars-Owe D
authors.initials: LO
authors.lastname: Koskinen