Outcome: Researchers from Center for Advanced Communications at Villanova University have developed an ultrasonic imaging technique that enables visualization of objects behind a screening layer.
Impact/Benefit: Ultrasonic imaging of tissues through another tissue or nondestructive evaluation of materials through a protective layer has been inconceivable. This is due to the layer induced reverberation clutter that overwhelms and obscures the scattering signatures of the objects of interests behind the layers. The researchers have developed a technique that eliminates such artifacts and renders visualization of objects possible. This advanced and effective imaging technique can be integrated into existing imaging systems to improve the diagnostic capability of medical ultrasound in challenging imaging scenarios as well as ultrasonic testing of materials in layered structures.
Explanation: Ultrasonic imaging or testing through a screening layer is hindered by strong reverberation clutter created within the layer as well as the layer’s ghosting effect on the objects of interest. The researchers used statistical signal models to exploit the clutter characteristics and design adaptive filters to eliminate the clutter and its ghosting effects. This novel technique will enable imaging of tissues or critical structures in traditionally challenging environments, such as brain imaging through the skull, flaw detection in materials coated with protective layers.

(a)

(b) (c)
Ultrasonic imaging of material flaws through a screening layer. Through-the-layer imaging experiment with a transducer array is shown in (a). The conventional imaging technique produces an image dominated by heavy clutter, as shown in (b), whereas the new imaging technique produces an image that clearly visualizes the two flaws, as shown in (c).


