This study is particularly important as misconceptions exist among some MRI users that scanners at higher field strengths are inherently more dangerous in terms of local implant heating. However, a comparative study examining the differential effects of resonant frequency on implant heating in the wide range of currently available MRI systems is missing. Įxtensive effort has been dedicated to assessing RF heating of elongated implants during MRI at 1.5 T and, to a lesser degree, at 3 T and above. Most patients with DBS devices, for example, can only undergo MRI at 1.5 T scanners with pulse sequences with substantially reduced power which are not optimal for target visualization. Therefore, the criteria under which patients with conductive implants are indicated for MRI are restrictive. Excessive tissue heating and serious thermal injuries could arise from this mechanism. This phenomenon, commonly known as the antenna effect, occurs when the electric field of the MRI transmit coil induces current on conductive lead wires, which raises the specific absorption rate (SAR) of the RF energy in the tissue surrounding the lead tips. Nevertheless, performing MRI in the presence of electronic implants that typically have elongated conductive leads is still challenging due to the risks associated with the radio frequency (RF) heating of implants. It is estimated that 50% to 75% of patients with cardiovascular implants or neuromodulation devices will require MRI during their lifetime, with many patients requiring repeated examinations. With MRI becoming increasingly prevalent, the number of cases in which patients with conductive implants are referred for an MRI exam increases. For example, MRI at 7 T can differentiate subsegments of the globus pallidus, a small brain nucleus that is the target of neuromodulation therapies, such as deep brain stimulation (DBS). There are strong incentives to do so: increasing the strength of the static magnetic field substantially increases the signal-to-noise ratio to visualize small structures previously unobservable on MRI scans.

Since the advent of MRI nearly four decades ago, there has been a race toward ever-increasing magnetic fields. Magnetic resonance imaging (MRI) has become a powerful imaging modality in the arsenal of noninvasive diagnostic tools, providing an unparalleled spatial resolution and soft-tissue contrast, as well as allowing to monitor functional changes in tissue. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.ĭata Availability: All relevant data are within the manuscript and its Supporting Information files.įunding: LG received funding from National Institute of Biomedical Imaging and Bioengineering (NIBIB) grant number: R01 EB030324 funder website: YE received funding from National Institute of Biomedical Imaging and Bioengineering (NIBIB) grant numbers: P41EB027061 and U01EB025144 funder website: The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Ĭompeting interests: The authors have declared that no competing interests exist. Received: Accepted: JanuPublished: January 26, 2023Ĭopyright: © 2023 Kazemivalipour et al. PLoS ONE 18(1):Įditor: Stephan Orzada, German Cancer Research Center: Deutsches Krebsforschungszentrum, GERMANY Citation: Kazemivalipour E, Sadeghi-Tarakameh A, Keil B, Eryaman Y, Atalar E, Golestanirad L (2023) Effect of field strength on RF power deposition near conductive leads: A simulation study of SAR in DBS lead models during MRI at 1.5 T-10.5 T.

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