title: Impact of imaging landmark on the risk of MRI-related heating near implanted medical devices like cardiac pacemaker leads.
abstract: Implanted medical devices such as cardiac pacemakers pose a potential hazard in magnetic resonance imaging. Electromagnetic fields have been shown to cause severe radio frequency-induced tissue heating in some cases. Imaging exclusion zones have been proposed as an instrument to reduce patient risk. The purpose of this study was to further assess the impact of the imaging landmark on the risk for unintended implant heating by measuring the radio frequency-induced electric fields in a body phantom under several imaging conditions at 1.5T. The results show that global radio frequency-induced coupling is highest with the torso centered along the superior-inferior direction of the transmit coil. The induced E-fields inside the body shift when changing body positioning, reducing both global and local radio frequency coupling if body and/or conductive implant are moved out from the transmit coil center along the z-direction. Adequate selection of magnetic resonance imaging landmark can significantly reduce potential hazards in patients with implanted medical devices.
authors.affiliation: Department of Internal Medicine I, University Hospital Würzburg, Julius-Maximilians-University, Würzburg, Germany. nordbeck_p@medizin.uni-wuerzburg.de
authors.forename: Peter
authors.initials: P
authors.lastname: Nordbeck
authors.forename: Oliver
authors.initials: O
authors.lastname: Ritter
authors.forename: Ingo
authors.initials: I
authors.lastname: Weiss
authors.forename: Marcus
authors.initials: M
authors.lastname: Warmuth
authors.forename: Daniel
authors.initials: D
authors.lastname: Gensler
authors.forename: Natalie
authors.initials: N
authors.lastname: Burkard
authors.forename: Volker
authors.initials: V
authors.lastname: Herold
authors.forename: Peter M
authors.initials: PM
authors.lastname: Jakob
authors.forename: Georg
authors.initials: G
authors.lastname: Ertl
authors.forename: Mark E
authors.initials: ME
authors.lastname: Ladd
authors.forename: Harald H
authors.initials: HH
authors.lastname: Quick
authors.forename: Wolfgang R
authors.initials: WR
authors.lastname: Bauer
mesh_terms: D002056:Burns / Q000209:etiology* / Q000517:prevention & control*; D004567:Electrodes, Implanted / Q000009:adverse effects*; D004868:Equipment Failure; D019544:Equipment Failure Analysis; D006358:Hot Temperature; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000009:adverse effects* / Q000295:instrumentation*; D010138:Pacemaker, Artificial / Q000009:adverse effects*; D019047:Phantoms, Imaging; D018570:Risk Assessment