Cylindrical Transducer Array for Intravascular Shear Wave Elasticity Imaging: Preliminary Development
Abstract
We present an intravascular ultrasound (IVUS) transducer array designed to enable shear wave elasticity imaging (SWEI) of arteries for the detection and characterization of atherosclerotic soft plaques. Using a custom dicing fixture, we have fabricated single-element and axially-segmented array transducer prototypes from 4.6-Fr to 7.6-Fr piezoceramic tubes, respectively. Focused excitation of the array prototype at 4 MHz yielded a focal gain of 5× in intensity, for an estimated 60 mW/cm2 I sppa and 1.6-MPa negative peak pressure at 4.5-mm range in water. The single-element transducer generated a peak radial displacement of 10.3 μ m in a uniform elasticity phantom, with axial shear waves detectable by an external linear array probe up to 5 mm away from the excitation plane. In a vessel phantom with a soft inclusion, the array prototype generated peak displacements of 2.2 and 0.5~ μ m in the soft inclusion and vessel wall regions, respectively. A SWEI image of the vessel phantom was reconstructed, with measured shear wave speed (SWS) of 1.66 ± 0.91 m/s and 0.97 ± 0.59 m/s for the soft inclusion and vessel wall regions, respectively. The array prototype was also used to obtain a SWEI image of an ex vivo porcine artery, with a mean SWS of 3.97 ± 1.12 m/s. These results suggest that a cylindrical intravascular ultrasound (IVUS) transducer array could be made capable of SWEI for atherosclerotic plaque detection in coronary arteries.
Publication Title
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
Recommended Citation
Telichko, A., Dahl, J., & Herickhoff, C. (2022). Cylindrical Transducer Array for Intravascular Shear Wave Elasticity Imaging: Preliminary Development. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 69 (3), 1077-1087. https://doi.org/10.1109/TUFFC.2022.3140976
