The feasibility of a new diagnostic imaging technique is investigated that potentially might be
used for breast cancer screening with millimeter resolution, but without using ionizing radiation. It
is suggested that acoustic pulses of sufficient intensity may produce small density changes within
tissue which result in small but detectable changes in electrical current flowing through the tissue.
The magnitude of this current fluctuation is shown to be inversely proportional to the conductivity
of the tissue within the region occupied by the pulse. Measurement of the current modulation may
enable small resistive inhomogeneities, such as tumors, to be detected. If the position of a pulse's
wavefront can be predicted with sufficient precision at any given instant, measurement of the
current modulation could be used to reconstruct the unknown electrical impedance distribution
within the tissue. The rudiments of the technique are discussed and, using some simplifying
assumptions, a rough estimate is made of the magnitude of the current modulation, and of the
timescale necessary to obtain useful diagnostic information.
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