title: Contrast Enhanced Superharmonic Imaging for Acoustic Angiography Using Reduced Form-Factor Lateral Mode Transmitters for Intravascular and Intracavity Applications.
abstract: Techniques to image the microvasculature may play an important role in imaging tumor-related angiogenesis and vasa vasorum associated with vulnerable atherosclerotic plaques. However, the microvasculature associated with these pathologies is difficult to detect using traditional B-mode ultrasound or even harmonic imaging due to small vessel size and poor differentiation from surrounding tissue. Acoustic angiography, a microvascular imaging technique that utilizes superharmonic imaging (detection of higher order harmonics of microbubble response), can yield a much higher contrast-to-tissue ratio than second harmonic imaging methods. In this paper, two dual-frequency transducers using lateral mode transmitters were developed for superharmonic detection and acoustic angiography imaging in intracavity applications. A single element dual-frequency intravascular ultrasound transducer was developed for concept validation, which achieved larger signal amplitude, better contrast-to-noise ratio (CNR), and pulselength compared to the previous work. A dual-frequency [Pb(Mg1/3Nb2/3)O3]-x[PbTiO3] array transducer was then developed for superharmonic imaging with dynamic focusing. The axial and lateral sizes of the microbubbles in a 200- [Formula: see text] tube were measured to be 269 and [Formula: see text], respectively. The maximum CNR was calculated to be 22 dB. These results show that superharmonic imaging with a low frequency lateral mode transmitter is a feasible alternative to thickness mode transmitters when the final transducer size requirements dictate design choices.
authors: Zhuochen
authors: Z
authors: Wang
authors: K
authors: K
authors: Heath Martin
authors: Wenbin
authors: W
authors: Huang
authors: Paul A
authors: PA
authors: Dayton
authors: Xiaoning
authors: X
authors: Jiang
mesh_terms: D000162:Acoustics / Q000295:instrumentation*; D000792:Angiography / Q000295:instrumentation*; D003287:Contrast Media / Q000737:chemistry*; D004867:Equipment Design; D006801:Humans; D045423:Microbubbles; D014159:Transducers; D014463:Ultrasonography / Q000295:instrumentation*
chemical_list: D003287:Contrast Media