Acousto-electric tomography

Abstract

Although the electric impedance of biological tissues is highly sensitive to their physiological and pathological status, pure electrical impedance tomography (EIT) has very poor spatial resolution. We invented acousto-electric tomography (AET) to image the electric impedance properties of biological tissues with high spatial resolution. AET is based on acousto-electric modulation, which is the localized variation in conductivity produced by a focused ultrasonic wave. It combines the contrast advantage of EIT and the resolution advantage of ultrasound imaging. The spatial resolution of AET is primarily defined by the size of the ultrasonic focal spot. Therefore, the resolution is much better than that of EIT, and it is scalable with the acoustic parameters. The contrast of AET is determined by the combination of three factors: the electric impedance, the media dependent modulation coefficient, and the acoustic properties. Unlike EIT, AET forms images directly without resorting to inverse algorithms. And unlike traditional ultrasonography, AET is free of speckles.