The influence of conductivity perturbations on MIT sensitivity field

Magnetic Induction Tomography (MIT) attempts to image conductivity distribution of biological tissues from pairs excitation and receiver coils. The inverse eddy current problem is nonlinear and ill-posed. Analysis of sensitivity field is necessary for image reconstruction. This study investigates the influence of conductivity perturbations, that is, changing the conductivity of a small region by a small amount, on the sensitivity field. Changes of sensitivity field relative to homogeneous conductivity background are calculated using finite-element method. The results show that the distribution of sensitivity field has relations with location and size of conductivity perturbations. This study provides the theoretical basis for image reconstruction.