Radio frequency versus susceptibility effects of small conductive implants — a systematic MRI study on aneurysm clips at 1.5 and 3 T

Lauer, Ulrike A.; Graf, Hansjörg; Berger, Alexander; Claussen, Claus D.; Schick, Fritz

doi:10.1016/j.mri.2005.02.012

Cited by 22 publications

(21 citation statements)

References 19 publications

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“…These artifacts are more pronounced on GE imaging than on TSE imaging due to the lack of the 180°refocusing pulse and increase with echo time due to the continued decay of transverse magnetization [3][4][5][6][7][8][9][10][11]. These findings have also been seen in our study when comparing susceptibility artifacts at a main magnetic field strength of 1.5 T and 3.0 T in various MR pulse sequences.…”

Section: In Vitro Findingssupporting

confidence: 79%

MR liver imaging and cholangiography in the presence of surgical metallic clips at 1.5 and 3 Tesla

et al. 2006

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To evaluate whether clips from prior cholecystectomy impair image quality during magnetic resonance cholangiography (MRC) at 3 Tesla (T) compared with 1.5 T, surgical clips were embedded in a gel phantom and positioned at predefined distances from a fluid-filled tube designed to simulate the bile duct. The maximum clip distance was noted where susceptibility artifacts obscured the fluid-filled tube at 1.5 T and 3 T. Susceptibility artifact size was calculated for each sequence within each magnet class. In vivo analysis included 42 patients postcholecystectomy who underwent MRC at either 1.5 T or 3 T. In vitro, mean area of susceptibility artifacts was 104 mm2 on 3-T and 75 mm2 on 1.5-T MR imaging (MRI). While surgical clips within a 2-mm range impaired visualization of the fluid-filled tube on 1.5-T MRI, this range increased to 4 mm on 3-T MRI. In vivo, MRC image quality was impaired by susceptibility artifacts in three of 21 cases at 3 T and in two of 21 cases at 1.5 T. Overall, biliary pseudo-obstructions due to susceptibility artifacts from cholecystectomy surgical clips were not substantially more common on 3-T MRC in clinical practice, and patients with a history of prior cholecystectomy should not be excluded from a 3-T MRC.

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Section: In Vitro Findingssupporting

confidence: 79%

MR liver imaging and cholangiography in the presence of surgical metallic clips at 1.5 and 3 Tesla

et al. 2006

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“…Understanding the origin of artefacts introduced into NMR images by conductors and susceptibility differences is of interest for both materials and medical imaging. [78,79] For example, magnetic susceptibility differences due to blood oxygen levels are responsible for the contrast observed in functional magnetic resonance imaging, fMRI.…”

mentioning

confidence: 99%

The Use of¹H NMR Microscopy to Study Proton‐Exchange Membrane Fuel Cells

2006

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To understand proton-exchange membrane fuel cells (PEMFCs) better, researchers have used several techniques to visualize their internal operation. This Concept outlines the advantages of using 1H NMR microscopy, that is, magnetic resonance imaging, to monitor the distribution of water in a working PEMFC. We describe what a PEMFC is, how it operates, and why monitoring water distribution in a fuel cell is important. We will focus on our experience in constructing PEMFCs, and demonstrate how 1H NMR microscopy is used to observe the water distribution throughout an operating hydrogen PEMFC. Research in this area is briefly reviewed, followed by some comments regarding challenges and anticipated future developments.

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“…Furthermore, metal suppression techniques only address susceptibility artefacts, leaving RF-induced artefacts an unsolved problem. Taking into account, lastly, the trend towards stronger static magnetic fields 13 , an increment of the importance of the RF-induced artefacts has been registered with a B 0 raise from 1.5 T to 3 T 9, 11, 14 in clinical platforms, because of the corresponding increment in the RF field frequency.…”

Section: Introductionmentioning

confidence: 93%

An ideal dielectric coat to avoid prosthesis RF-artefacts in Magnetic Resonance Imaging

Zanovello

Matekovits

Zilberti

2017

Sci Rep

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The number of people submitted to total hip or knee arthroplasty increased in the last years and it is likely to grow further. Hence, the importance of a proper investigation tool that allows to determine and recognize the potential presence of perioperative and/or postoperative diseases becomes clear. Although the Magnetic Resonance Imaging (MRI) technique demonstrated several advantages over the other common tomography tools, it suffers from the arise of image artefacts if it is performed in presence of metallic prostheses. In particular, the so-called RF-artefacts are caused by the inhomogeneity in the radiofrequency magnetic field of MRI, due to the electric currents induced on the metal surface by the field itself. In this work, a near-zero permittivity dielectric coat is simulated to reduce those currents and, therefore, the RF-artefacts onset in the final image. Numerical results confirm that the dielectric coat strongly reduces the magnetic field inhomogeneity, suggesting a possible solution to a well-known problem in the MRI field.

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Radio frequency versus susceptibility effects of small conductive implants — a systematic MRI study on aneurysm clips at 1.5 and 3 T

Cited by 22 publications

References 19 publications

MR liver imaging and cholangiography in the presence of surgical metallic clips at 1.5 and 3 Tesla

MR liver imaging and cholangiography in the presence of surgical metallic clips at 1.5 and 3 Tesla

The Use of¹H NMR Microscopy to Study Proton‐Exchange Membrane Fuel Cells

An ideal dielectric coat to avoid prosthesis RF-artefacts in Magnetic Resonance Imaging

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Radio frequency versus susceptibility effects of small conductive implants — a systematic MRI study on aneurysm clips at 1.5 and 3 T

Cited by 22 publications

References 19 publications

MR liver imaging and cholangiography in the presence of surgical metallic clips at 1.5 and 3 Tesla

MR liver imaging and cholangiography in the presence of surgical metallic clips at 1.5 and 3 Tesla

The Use of1H NMR Microscopy to Study Proton‐Exchange Membrane Fuel Cells

An ideal dielectric coat to avoid prosthesis RF-artefacts in Magnetic Resonance Imaging

Contact Info

Product

Resources

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The Use of¹H NMR Microscopy to Study Proton‐Exchange Membrane Fuel Cells