Title: Robust Computation in 2D Absolute EIT (a-EIT) Using D-bar Methods with the `exp' Approximation,
Abstract: Objective: Absolute images have important applications in medical Electrical
Impedance Tomography (EIT) imaging, but the traditional minimization and
statistical based computations are very sensitive to modeling errors and noise.
In this paper, it is demonstrated that D-bar reconstruction methods for
absolute EIT are robust to such errors. Approach: The effects of errors in
domain shape and electrode placement on absolute images computed with 2D D-bar
reconstruction algorithms are studied on experimental data. Main Results: It is
demonstrated with tank data from several EIT systems that these methods are
quite robust to such modeling errors, and furthermore the artefacts arising
from such modeling errors are similar to those occurring in classic
time-difference EIT imaging. Significance: This study is promising for clinical
applications where absolute EIT images are desirable, but previously thought
impossible.