Electrical impedance endotomography: sensitivity distribution against bipolar current patterns.
Electrical impedance endotomography (EIE) is a modality where the electrodes are located around an insulating core placed inside the region of interest. This approach results in significant differences with respect to conventional EIT. The paper examines the sensitivity distribution of bipolar current patterns and the influence of the spacing between the drive electrodes using a two-dimensional (2D) mathematical model. The number of pixels of sensitivity above a given sensitivity threshold decreases faster with the distance to the probe for diametric and adjacent drive than for other bipolar drive patterns. The reconstruction of images from datasets collected in vitro using a 16-electrode probe confirmed the feasibility of the method at least within a range extending to three times the radius of the probe, under the described experimental conditions. Reduction of system noise, multiple-current patterns and the use of remote current and voltage electrodes are potential methods to increase the sensitivity range. Further work includes the improvement of the model to account for finite length electrodes and the miniaturization of the probe.
National Institute for Health and Medical Research, INSERM, 151 Cours Albert Thomas, 69424 Lyon Cedex 03, France.
Jacques
J
Jossinet
Anne
A
Desseux
D016477:Artifacts; D004553:Electric Conductivity; D017097:Electric Impedance; D006801:Humans; D008297:Male; D008954:Models, Biological; D011467:Prostate; D012680:Sensitivity and Specificity; D014054:Tomography / Q000379:methods*