MAGNETIC RESONANCE

CURRENT DENSITY IMAGING

MRCDI

Images of non-uniform and uniform electric current density in conductor phantoms are produced using Magnetic Resonance Imaging (MRI). A standard spin echo pulse sequence is used, in addition with a bipolar current pulse applied to the phantom in synchrony with the pulse sequence. The flux density parallel to the main imaging field, generated by the current pulse, encoded in the phase of the complex MR image. The spatial distribution of magnetic flux density can therefore be extracted from the phase image. Current density is calculated by knowing the magnetic flux density, using Ampere's law. Current densities less than 2 milliAmperes per meter square are measured.

Current density imaging may have potential biomedical applications in understanding externally applied electric fields to the body (e.g. defibrillation fields) and measurement of lead-sensitivity maps for bio-electric imaging. Since biological tissues have different electrical properties, it may be possible to obtain anatomical and functional information from current density images.

This project is a collaborative work with University of Pennsylvania, Philadelphia - U.S.A.

Reference:
O. Ozbek, O. Birgul, B.M. Eyuboglu and Y.Z. Ider, "Imaging Electrical Current Density Using 0.15 Tesla Magnetic Resonance Imaging
System," Proceedings (CD-ROM) of the IEEE/EMBS 23rd Annual Conference, Istanbul - Turkey, 2001. article.pdf ; poster.pdf

Eyuboglu BM, Reddy R and Leigh JS, 1998, "Imaging Electric Current Density using Nuclear Magnetic Resonance," ELEKTRIK, Vol.6,
No.3, pp.201-14. article.pdf

Eyuboglu BM, Reddy R and Leigh JS, 1996, "Measurement of Current Density with MRI," IEEE Medical Imaging Conference, Anaheim CA.

Eyuboglu BM, Reddy R and Leigh JS, 1996, "Imaging Electric Current Density using Magnetic Resonance Imaging," 82nd Scientific Assembly and Annual Meeting of Radiological Society of North America, Chicago IL.