Published in Physics World, 28 Nov 2012
Physicists in China say they have made a breakthrough in thermoacoustic imaging that could enable it to be used in hospitals within five years. The technique, which involves firing microwaves at tissue, had previously been considered too dangerous to use on humans, but the researchers have now employed what they say is a safer, nanosecond microwave source.
Thermoacoustic imaging was invented in the early 1980s. The idea is to expose tissue to a microwave pulse, which travels into the tissue until it is absorbed. Exactly how the pulse is absorbed depends on the type of tissue present. When the pulse is absorbed, it does not heat the tissue significantly because it is very short. The energy instead generates a moving deformation, which is an acoustic wave. The profile of this acoustic wave is detected using an array of transducers, and these data are used to create an image of the tissue through which the microwave pulse has passed. […]
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