Safety of MRI in patients with retained cardiac leads.

Autor: Nguyen BT; Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA., Bhusal B; Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA., Rahsepar AA; Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA., Fawcett K; Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA., Lin S; Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA., Marks DS; Department of Electrophysiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA., Passman R; Department of Electrophysiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA., Nieto D; Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA., Niemzcura R; Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA., Golestanirad L; Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.; Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, Illinois, USA.
Jazyk: angličtina
Zdroj: Magnetic resonance in medicine [Magn Reson Med] 2022 May; Vol. 87 (5), pp. 2464-2480. Date of Electronic Publication: 2021 Dec 27.
DOI: 10.1002/mrm.29116
Abstrakt: Purpose: To evaluate the safety of MRI in patients with fragmented retained leads (FRLs) through numerical simulation and phantom experiments.
Methods: Electromagnetic and thermal simulations were performed to determine the worst-case RF heating of 10 patient-derived FRL models during MRI at 1.5 T and 3 T and at imaging landmarks corresponding to head, chest, and abdomen. RF heating measurements were performed in phantoms implanted with reconstructed FRL models that produced highest heating in numerical simulations. The potential for unintended tissue stimulation was assessed through a conservative estimation of the electric field induced in the tissue due to gradient-induced voltages developed along the length of FRLs.
Results: In simulations under conservative approach, RF exposure at B 1 + ≤ 2 µT generated cumulative equivalent minutes (CEM) 43 < 40 at all imaging landmarks at both 1.5 T and 3 T, indicating no thermal damage for acquisition times (TAs) < 10 min. In experiments, the maximum temperature rise when FRLs were positioned at the location of maximum electric field exposure was measured to be 2.4°C at 3 T and 2.1°C at 1.5 T. Electric fields induced in the tissue due to gradient-induced voltages remained below the threshold for cardiac tissue stimulation in all cases.
Conclusions: Simulation and experimental results indicate that patients with FRLs can be scanned safely at both 1.5 T and 3 T with most clinical pulse sequences.
(© 2021 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.)
Databáze: MEDLINE
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