Computed tomography with microwaves.

Abstract

Computed tomographic images were generated using collimated microwaves of frequency 10.5 GHz instead of x rays. In the authors' laboratory version of a rotate-translate scanner, the beam is fixed and a phantom is moved between source and detector, the apparatus being suspended in a tank of fluid to provide impedance matching between phantom, source, and receiver. Phantoms consisting of test tubes of water, cylinders of wood, and animal tissues show spatial resolutions of about 2 cm. It is planned to apply the technique first to mammographic examination, which can best utilize the large difference in microwave absorption between fatty and nonfatty tissues.