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PubMed · 12815700

Electromagnetic actuator for generating variably oriented shear waves in MR elastography.

Juergen Braun·Karl Braun·Ingolf Sack
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Abstract

Magnetic resonance elastography (MRE) is a recently developed technique for determining the mechanical properties of biological tissue. In dynamic MRE, electromagnetic units (actuators) are widely used to generate shear waves in tissue. These actuators exploit the interaction between the static magnetic field B(0) and an annular coil supplied with alternating currents. Therefore, coil movements are restricted to selected orientations to B(0). Conventional actuators transfer this movement collinearly to B(0) into the tissue. In this study, an electromagnetic actuator was introduced that overcomes this limitation. It is demonstrated that different directions of mechanical excitation can be generated and monitored by MRE. Different spatial components of the propagation of the shear waves were determined using agarose phantoms. The technique allows maximum contrast for MRE images of objects with anisotropic strain components such as muscle tissue.

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AnisotropyElasticityEquipment DesignEquipment Failure AnalysisMagnetic Resonance ImagingMagneticsMicromanipulationMotionMuscle, SkeletalPhysical StimulationShear StrengthVibrationComparative StudyEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov'tValidation Study

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Juergen Braun, Karl Braun, Ingolf Sack. 2003. Electromagnetic actuator for generating variably oriented shear waves in MR elastography.. https://doi.org/10.1002/mrm.10479

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