An ultrasonic microbubble semi-intermodulated imaging technique.

Chung-Yuo Wu; Jenho Tsao; Yi-Hong Chou

doi:10.1016/j.ultrasmedbio.2005.04.015

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PubMed · 16176787

An ultrasonic microbubble semi-intermodulated imaging technique.

Chung-Yuo Wu·Jenho Tsao·Yi-Hong Chou

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Abstract

The performance of contrast imaging technique is critically influenced by some factors, such as spatial resolution, agent-to-tissue ratio, lifetime of contrast agents and attenuation effect. By using a transducer with higher frequency and higher bandwidth of transmitted signals, the spatial resolution can be improved. Similarly, a better signal-to-interference ratio (SIR) can improve the agent-to-tissue ratio, a lower transmission pressure can prolong the lifetime of contrast agents and a lower center frequency can diminish the attenuation effect. We extend the two-frequency analytic solutions of to approximate the short-pulse responses of microbubbles in a low-amplitude field. Based on their results, there is an expected component near 0 Hz in the spectrum of bubble echoes excited by a short pulse of ultrasound. Here, this component is called the low-frequency response; and it is shown to have a special bandwidth-dependent property and to have potential applications in imaging. We have established the procedure of semi-intermodulated (low-frequency) imaging and the effects of the attenuation effect on imaging resolution, SIR, and signal-to-noise ratio are also analyzed. The obtained experimental images demonstrate that the SIR in semi-intermodulated imaging is better than that in fundamental imaging under various attenuation conditions.

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Contrast Media Humans Image Processing, Computer-Assisted Microbubbles Phantoms, Imaging Ultrasonography Evaluation Study Journal Article Research Support, Non-U.S. Gov't

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Chung-Yuo Wu, Jenho Tsao, Yi-Hong Chou. 2005. An ultrasonic microbubble semi-intermodulated imaging technique.. https://doi.org/10.1016/j.ultrasmedbio.2005.04.015

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