Microwave medical imaging techniques

Medical imaging utilizing electromagnetic waves as probes has been studied for at least the past half century, and, despite its long gestation period, in recent years it has finally claimed its proper role as an emerging alternative to X-rays. These evolving electromagnetic techniques now embrace several varieties of bioinstrumentation, microwave thermography and microwave microscopy, radar imaging, microwave holography, diffraction tomography, and on to inverse scattering methods, the latter largely reliant upon an optimization-based, computer-intensive underpinning. Our survey will conclude with a comprehensive comparison roster. In 2004 we developed the Field Mapping Algorithm (FMA) in the arena of electromagnetic fields. In addition to its natural antenna and radar cross section (RCS) applications, we have recently found it to be ideally suited for use in medical imaging. Our FMA provides direct solutions to 3-D inverse scattering problems, allowing images of internal biological organs to be obtained simply on the basis of the scattered fields detected by sensors that are proximate, yet fully external to living tissue. In particular, with the low-power microwave probing which is organized beneath the control of our FMA, one is able to bypass altogether the carcinogenic threat of in situ ionization which inevitably accompanies X-ray transit. Test measurements conducted with bona fide biological samples have consistently shown convincing results.