title: Measurement of ion diffusion using magnetic resonance electrical impedance tomography.
abstract: In magnetic resonance electrical impedance tomography (MREIT), currents are applied to an object, the resulting magnetic flux density measured using MRI and the conductivity distribution reconstructed using these MRI data. In this study, we assess the ability of MREIT to monitor changes in the conductivity distribution of an agarose gel phantom, using injected current pulses of 900 microA. The phantom initially contained a distinct region of high sodium chloride concentration which diffused into the background over time. MREIT data were collected over a 12 h span, and conductivity images were reconstructed using the iterative sensitivity matrix method with Tikhonov regularization. The results indicate that MREIT was able to monitor the changing conductivity and concentration distributions resulting from the diffusion of ions within the agarose gel phantom.
authors.affiliation: Tu & Yuen Center for Functional Onco-Imaging, University of California, 164 Irvine Hall, Irvine, CA 92697-5020, USA. markjham@uci.edu
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Hamamura
authors.forename: L Tugan
authors.initials: LT
authors.lastname: Muftuler
authors.forename: Ozlem
authors.initials: O
authors.lastname: Birgul
authors.forename: Orhan
authors.initials: O
authors.lastname: Nalcioglu
mesh_terms: D000465:Algorithms; D004058:Diffusion; D004553:Electric Conductivity; D017097:Electric Impedance; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007477:Ions; D008279:Magnetic Resonance Imaging / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012685:Sepharose / Q000737:chemistry; D012965:Sodium Chloride / Q000494:pharmacology; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D007477:Ions; D012965:Sodium Chloride; D012685:Sepharose