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PubMed · 10053158

Current-induced magnetic resonance phase imaging.

J Bodurka·A Jesmanowicz·J S Hyde·H Xu·L Estkowski·S J Li
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Abstract

Electric current-induced phase alternations have been imaged by fast magnetic resonance image (MRI) technology. We measured the magnetic resonance phase images induced by pulsed current stimulation from a phantom and detected its sensitivity. The pulsed current-induced phase image demonstrated the feasibility to detect phase changes of the proton magnetic resonance signal that could mimic neuronal firing. At the present experimental setting, a magnetic field strength change of 1.7 +/- 0.3 nT can be detected. We also calculated the averaged value of the magnetic flux density BT parallel to B0 produced by electric current I inside the voxel as a function of the wire position. The results of the calculation were consistent with our observation that for the same experimental setting the current-induced phase change could vary with location of the wire inside the voxel. We discuss our findings in terms of possible direct MRI detection of neuronal activity.

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Evoked PotentialsFeasibility StudiesHumansImage Processing, Computer-AssistedMagnetic Resonance ImagingMagneticsNeuronsPhantoms, ImagingComparative StudyJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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J Bodurka, A Jesmanowicz, J S Hyde, H Xu, L Estkowski, S J Li. 1999. Current-induced magnetic resonance phase imaging.. https://doi.org/10.1006/jmre.1998.1680

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