Intravascular ultrasound tissue harmonic imaging in vivo

Nonlinear intravascular ultrasound contrast imaging

“…2b for five of the 20 MHz transmit pressures. The H40 signal builds until approximately the 3.5 to 5 mm range, and then decreases, a pattern similar to that reported in Frijlink et al (2004). The peak H40 signal level can also be seen to increase steeply as a function of transmit pressure.…”

“…The peak H40 signal level can also be seen to increase steeply as a function of transmit pressure. These signals are exploited in Frijlink et al (2004) for the purposes of tissue harmonic imaging by using high transmit amplitudes. In the present study, nonlinear propagation will act to degrade the performance of H40 contrast imaging.…”

“…The configuration employed in tissue harmonic imaging is described and evaluated in Frijlink et al (2004). A block diagram overview of the arrangement for contrast agent imaging is shown in Fig.…”

Transducer for harmonic intravascular ultrasound imaging

“…Initial studies have shown the feasibility of THI in IVUS imaging [6], [7], but these were carried out with transducers that were not optimized for THI. Various fundamental and harmonic imaging transducers for diagnostic medical high-frequency ultrasound are described in the literature [3], [8]- [10], mostly based on PVDF and lithium niobate.…”

Nonlinear imaging of targeted microbubbles with intravascular ultrasound

“…We employed a prototype harmonic IVUS system, which was developed to perform both tissue harmonic [4] and contrast agent harmonic imaging [3]. The apparatus adapts a commercial single element mechanical scanning system (DuMed, Rotterdam, the Netherlands).…”