Microwave imaging for neoadjuvant chemotherapy monitoring

We have developed a clinical microwave imaging system for breast imaging applications including cancer detection and monitoring of neoadjuvant chemotherapy. For the latter, key features of any montoring system must include the ability to image a target in a repeatable fashion while being noninvasive and relatively inexpensive. Our microwave imaging system is particularly useful in this setting because we have overcome challenges such as the use of a priori information with the combination of our unique imaging configuration and software. The hardware incorporates monopole antennas which present isotropically radiated fields within which complex nulls (and accompanying non-unique signal phase distributions) are generally not generated until the electromagnetic wave has propagated beyond the illumination zone and associated receiver antennas. This is particularly useful for our variance stabilizing transformation algorithm which can recover accurate dielectric property maps without a priori information or converging to local minima as long as the unwrapped phase distribution remains unique. The associated unwrapping of the measurement data can be readily performed through the use of multi-frequency data and standard unwrapping algorithms.