New ultrasound technique ‘can penetrate bone and metal’

Researchers in the US have found a new way of improving the penetration of ultrasound waves, potentially creating new imaging and treatment benefits.

The North Carolina State University team have designed customised metamaterial structures that take into account the acoustic properties of aberrating layers – such as bone or metal – that block or distort ultrasound waves, thus helping to offset this effect.

In simulations, only 28 percent of ultrasound wave energy made it past an aberrating layer of bone, but with the metamaterial structure in place, 88 percent of the energy was able to penetrate through the bone.

Tarry Chen Shen, a PhD student at NC State and lead author on the paper, said this innovation "will make it easier for medical professionals to use ultrasound for diagnostic or therapeutic applications, such as monitoring blood flow in the brain or to treat brain tumours".

This method also has industrial applications, such as for the detection of hidden cracks within the metal wings of aeroplanes.

Such innovations will help to further increase the utility of ultrasound, which is already one of the most important medical imaging and treatment tools.