Electromagnetic Field Mechanisms and Safety Implications in Magnetic Resonance Imaging: A Contemporary Review
Keywords:
Electromagnetic Fields , MRI Principles , MRI Safety, Radiofrequency Fields, Risk AssessmentAbstract
Magnetic resonance imaging (MRI) relies on static, gradient, and radiofrequency (RF) electromagnetic fields to generate high-resolution diagnostic images. As MRI technology continues to advance, comprehensive knowledge of these fields is increasingly important for safe and effective clinical practice. However, existing evidence remains fragmented, while limited technical understanding may affect protocol selection, implant assessment, patient handling, and risk management. Therefore, this review aims to explain the principles of MRI electromagnetic fields, examine their effects on image formation, system performance, interactions with biological tissue, and implanted medical devices, and synthesise current evidence on their associated safety implications. An integrative narrative review was conducted using structured literature searches, followed by narrative and matrix synthesis of 40 sources including review articles, experimental and simulation studies, clinical investigations, safety guidelines, consensus statements, and organisational studies. The findings indicate that static magnetic fields facilitate nuclear alignment but introduce projectile, vestibular, and implant-displacement hazards. Gradient magnetic fields provide spatial encoding but may induce peripheral nerve stimulation, cardiac magnetostimulation, and acoustic exposure, whereas RF fields enable proton excitation while presenting tissue-heating and implant-related thermal risks. MRI safety is influenced by multiple interacting factors, including scanner configuration, implant characteristics, patient anatomy, operating conditions, staff competency, and institutional governance. Integrating electromagnetic-field principles with evidence-based system design, rigorous safety protocols, and patient-specific risk assessment is essential for ensuring high-quality imaging while minimising patient and occupational risks.
References
L. Mittendorff, A. Young, and J. Sim, “A narrative review of current and emerging MRI safety issues: What every MRI technologist (radiographer) needs to know,” Journal of Medical Radiation Sciences, vol. 69, no. 2, pp. 250–260, Jun. 2022, doi: 10.1002/jmrs.546.
M. Tang and T. Yamamoto, “Progress in understanding radiofrequency heating and burn injuries for safer MR imaging,” Magnetic Resonance in Medical Sciences, vol. 22, no. 1, pp. 7–25, 2023, doi: 10.2463/mrms.rev.2021-0047.
A. S. Afolabi, “A review of radiofrequency-induced heating challenge caused to medical implants during MRI procedures,” Journal of Electrical Systems and Information Technology, vol. 12, Sep. 2025, Art. no. 74, doi: 10.1186/s43067-025-00264-3.
T. Okada, T. Akasaka, D. H. D. Thuy, and T. Isa, “Safety for human MR scanners at 7T,” Magnetic Resonance in Medical Sciences, vol. 21, no. 4, pp. 531–537, 2021, doi: 10.2463/mrms.rev.2021-0063.
B. Moyer, “An overview of medical imaging,” Mouser Electronics, 2020. [Online]. Available: https://br.mouser.com/applications/medical-imaging-overview/
R. Babaloo and E. Atalar, “Minimizing electric fields and increasing peripheral nerve stimulation thresholds using a body gradient array coil,” Magnetic Resonance in Medicine, vol. 92, no. 3, pp. 1290–1305, Apr. 2024, doi: 10.1002/mrm.30109.
R. Rupp, M. Balk, M. Sievert, V. Leibl, S. Schleder, M. Allner, H. Iro, U. Hoppe, J. Hornung, and A. Oreste, “Risk of MRI-induced magnet dislocation for different types of cochlear implants: A single-center retrospective study,” Journal of Otolaryngology–Head & Neck Surgery, vol. 52, Apr. 2023, Art. no. 28, doi: 10.1186/s40463-023-00633-w.
F. G. Shellock, M. S. Rosen, A. Webb, W. T. Kimberly, S. Rajan, A. N. Nacev, and J. V. Crues, “Managing patients with unlabeled passive implants on MR systems operating below 1.5T,” Journal of Magnetic Resonance Imaging, vol. 59, no. 5, pp. 1514–1522, Sep. 2023, doi: 10.1002/jmri.29002.
J. Kihlberg, B. Hansson, A. Hall, A. Tisell, and P. Lundberg, “Magnetic resonance imaging incidents are severely underreported: A finding in a multicentre interview survey,” European Radiology, vol. 32, no. 1, pp. 477–488, Jul. 2021, doi: 10.1007/s00330-021-08160-w.
European Society of Radiology, “The European MR safety landscape,” Insights into Imaging, vol. 15, Oct. 2024, Art. no. 238, doi: 10.1186/s13244-024-01813-6.
D. Alkhulaifat, L. Vidal, E. Larsen, S. D. Serai, M. S. Ycochea, P. Mecca, L. Orfe, and S. T. Sotardi, “MRI safety-developing the right culture,” Pediatric Radiology, vol. 55, no. 5, pp. 895–901, 2025, doi: 10.1007/s00247-025-06179-5.
S. T. Sotardi, A. J. Degnan, C. A. Liu, P. L. Mecca, S. D. Serai, R. D. Smock, T. Victoria, and A. M. White, “Establishing a magnetic resonance safety program,” Pediatric Radiology, vol. 51, no. 5, pp. 709–715, 2021, doi: 10.1007/s00247-020-04910-y.
M. Harwood, S. J. Fahrenholtz, C. V. Wellnitz, A. Kawashima, and A. Panda, “MRI in adult patients with active and inactive implanted MR-conditional, MR-nonconditional, and other devices,” Radiographics, vol. 44, no. 3, 2024, Art. no. e230102, doi: 10.1148/rg.230102.
B. Bhusal, J. Stockmann, B. Guerin, A. Mareyam, J. Kirsch, L. L. Wald, M. J. Nolt, J. Rosenow, R. L. Rosado, B. Elahi, and L. Golestanirad, “Safety and image quality at 7 T MRI for deep brain stimulation systems: Ex vivo study with lead-only and full systems,” PLoS ONE, vol. 16, no. 9, 2021, Art. no. e0257077, doi: 10.1371/journal.pone.0257077.
G. Zandieh, I. Yazdaninia, S. Afyouni, A. Borhani, T. Yokoo, and I. R. Kamel, “Updates on the MR safety guidelines – Essentials for radiologists,” Clinical Imaging, vol. 118, 2024, Art. no. 110394, doi: 10.1016/j.clinimag.2024.110394.
C. Meier, I. Carsten, M. Eisenblätter, A. Hoyer, F. V. Stoye, A. Yilmaz, and S. Gielen, “Safety of magnetic resonance imaging in patients with cardiac implantable electronic devices and abandoned or epicardial leads: A systematic review and meta-analysis,” EP Europace, vol. 26, no. 6, Jun. 2024, Art. no. euae165, doi: 10.1093/europace/euae165.
L. Shtrepi, V. F. D. Poggetto, C. Durochat, M. Dubois, D. Bendahan, F. Nistri, M. Miniaci, N. M. Pugno, and F. Bosia, “Acoustic noise levels and field distribution in 7 T MRI scanners,” Frontiers in Physics, vol. 11, Nov. 2023, Art. no. 1284659, doi: 10.3389/fphy.2023.1284659.
M. Uramatsu, H. Takahashi, P. Barach, Y. Fujisawa, M. Takahashi, S. Mishima, and G. Yamanaka, “Improving pediatric magnetic resonance imaging safety by enhanced non-technical skills and team collaboration,” Brain and Development, vol. 47, no. 1, Feb. 2025, Art. no. 104311, doi: 10.1016/j.braindev.2024.104311.
D. Kim et al., “SCMR expert consensus statement for cardiovascular magnetic resonance of patients with a cardiac implantable electronic device,” Journal of Cardiovascular Magnetic Resonance, vol. 26, no. 1, 2024, Art. no. 100995, doi: 10.1016/j.jocmr.2024.100995.
R. J. Russo, L. G. Smith, U. M. B. Green, J. K. Han, A. D. Krah, T. R. Larsen, H. I. Litt, C. F. Liu, S. Nazarian, P. K. Woodard, E. S. Zado, and J. N. Koneru, “HRS call-to-action: Improved MRI access for patients with cardiovascular implantable electronic devices,” Heart Rhythm, vol. 22, no. 9, pp. e821–e836, Sep. 2025, doi: 10.1016/j.hrthm.2025.04.028.
M. J. McJury, “Acoustic noise and magnetic resonance imaging: A narrative/descriptive review,” Journal of Magnetic Resonance Imaging, vol. 55, no. 2, pp. 337–346, 2021, doi: 10.1002/jmri.27525.
F. Hadziahmetovic, A. A. Almisreb, C. Z. C. Hasan, and A. Cantelli-Forti, “AI in brain tumour detection: Comparative analysis of YOLOv10 and PaliGemma2 with public perception insights in Bosnia and Herzegovina,” Politeknik & Kolej Komuniti Journal of Engineering and Technology, vol. 10, no. 2, pp. 12–24, Nov. 2025.
M. Hori, A. Hagiwara, M. Goto, A. Wada, and S. Aoki, “Low-field magnetic resonance imaging: Its history and renaissance,” Investigative Radiology, vol. 56, no. 11, pp. 669–679, 2021, doi: 10.1097/rli.0000000000000810.
T. C. Arnold, C. W. Freeman, B. Litt, and J. M. Stein, “Low-field MRI: Clinical promise and challenges,” Journal of Magnetic Resonance Imaging, vol. 57, no. 1, pp. 25−44, 2023, doi: 10.1002/jmri.28408.
V. Klein et al., “Simulation of dB/dt-over-electric field cardiac magnetostimulation safety ratios in 75 body models and 18 gradient systems,” Magnetic Resonance in Medicine, vol. 95, no. 3, pp. 1753–1761, 2026, doi: 10.1002/mrm.70130.
M. Davids et al., “Peripheral nerve stimulation informed design of a high-performance asymmetric head gradient coil,” Magnetic Resonance in Medicine, vol. 90, no. 2, pp. 784–801, 2023, doi: 10.1002/mrm.29668.
N. Boulant et al., “Acoustic noise reduction in the NexGen 7 T scanner,” Magnetic Resonance in Medicine, vol. 92, no. 5, pp. 2261–2270, 2024, doi: 10.1002/mrm.30211.
B. Silemek et al., “Rapid safety assessment and mitigation of radiofrequency induced implant heating using small root mean square sensors and the sensor matrix Qs,” Magnetic Resonance in Medicine, vol. 87, no. 1, pp. 509–527, 2022, doi: 10.1002/mrm.28968.
E. Kazemivalipour et al., “Vertical open-bore MRI scanners generate significantly less radiofrequency heating around implanted leads: A study of deep brain stimulation implants in 1.2 T OASIS scanners versus 1.5 T horizontal systems,” Magnetic Resonance in Medicine, vol. 86, no. 3, pp. 1560–1572, 2021, doi: 10.1002/mrm.28818.
B. T. Nguyen et al., “Safety of MRI in patients with retained cardiac leads,” Magnetic Resonance in Medicine, vol. 87, no. 5, pp. 2464–2480, 2022, doi: 10.1002/mrm.29116.
M. J. Greenhill et al., “MRI in patients with cardiovascular implantable electronic devices and fractured or abandoned leads,” Radiology: Cardiothoracic Imaging, vol. 6, no. 3, 2024, Art. no. e230303, doi: 10.1148/ryct.230303.
P. Jacobs and A. J. Fagan, “The effect of frequency (64–498 MHz) on specific absorption rate adjacent to metallic orthopedic screws in MRI: A numerical simulation study,” Medical Physics, vol. 51, no. 2, pp. 1074–1082, 2024, doi: 10.1002/mp.16902.
M. Arianpouya, B. Yang, F. Tam, C. E. McElcheran, and S. J. Graham, “Optimized radiofrequency shimming using low-heating B1+-mapping in the presence of deep brain stimulation implants: Proof of concept,” PLoS ONE, vol. 19, no. 12, 2024, Art. no. e0316002, doi: 10.1371/journal.pone.0316002.
N. Karadeniz, J. V. Hajnal, and Ö. İpek, “Design of multi-row parallel-transmit coil arrays for enhanced SAR efficiency with deep brain electrodes at 3T: An electromagnetic simulation study,” Magnetic Resonance Materials in Physics, Biology and Medicine, vol. 38, no. 1, pp. 107–120, 2025, doi: 10.1007/s10334-024-01212-4.
N. Kutscha et al., “A deep brain stimulation-conditioned RF coil for 3T MRI,” Magnetic Resonance in Medicine, vol. 93, no. 3, pp. 1411–1426, 2025, doi: 10.1002/mrm.30331.
B. Bhusal et al., “Comparative study of radiofrequency heating in deep brain stimulation devices during MRI at 1.5 T and 0.55 T: Challenging the assumption of safety at low field strengths,” Magnetic Resonance in Medicine, vol. 94, no. 2, pp. 785–796, 2025, doi: 10.1002/mrm.30515.
M. M. Mustafa et al., “On the RF safety of titanium mesh head implants in 7 T MRI systems: An investigation,” Magnetic Resonance in Medicine, vol. 94, no. 1, pp. 414–423, 2025, doi: 10.1002/mrm.30477.
M. K. Akter, A. Shen, M. Z. Islam, L. Zhang, J. Zheng, and J. Chen, “Numerical and experimental study of RF-induced heating of passive implantable medical devices at 5T MRI,” Magnetic Resonance in Medicine, vol. 94, no. 6, pp. 2632–2642, 2025, doi: 10.1002/mrm.70024.
C. Hartmann, M. Bouldi, and J. M. Warnking, “Assessing radiofrequency safety of active implants by measuring induced radiofrequency currents using MRI,” Magnetic Resonance in Medicine, vol. 95, no. 2, pp. 868–880, 2026, doi: 10.1002/mrm.70084.
G. Fierens, M. Clemence, N. Verhaert, R. Bowtell, and R. S. Dewey, “The safety of active hearing implants in the ultra-high field magnetic resonance environment: A pilot study,” Otology & Neurotology, vol. 46, no. 10, pp. 1338–1345, 2025, doi: 10.1097/MAO.0000000000004638.
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2026 Politeknik & Kolej Komuniti Journal of Engineering and Technology
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
