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.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Braun J,Braun K,Sack Idoi
10.1002/mrm.10479subject
Has Abstractpub_date
2003-07-01 00:00:00pages
220-2issue
1eissn
0740-3194issn
1522-2594journal_volume
50pub_type
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