  In this paper we estimate the size of a measurable inclusion in terms of
power measurements for a single applied boundary current. This problem arises
in medical imaging for the screening of organs. For this kind of problem one
has to deal mathematically with the complex conductivity (admittivity)
equation. In this case we are able to establish, for certain classes of
admittivities, lower and upper bounds of the measure of the inclusion in terms
of the power measurements. A novelty of our result is that we are able to
estimate also the volume of inclusions having part of its boundary in common
with the reference body. Our analysis is based on the derivation of energy
bounds and of fine quantitative estimates of unique continuation for solutions
to elliptic equations.
