[Advanced Dynamic Flow]
There are problems for contrast imaging using LevovistTM contrast agent. In case of Doppler mode, poor resolution and large blooming area are the problems. In case of 2nd harmonic imaging and pulse inversion imaging, tissue harmonic image(THI) becomes the problem because Levovist needs high mechanical index(MI). THI increases under the high MI condition and THI interferes with the contrast image of Levovist. And also bubbles of Levovist are easily collapsed under the high MI condition, so it is hard to visualize the bubbles successively. Dynamic Flow has solved the above problems. Dynamic Flow uses Doppler technique, but Dynamic Flow image has higher resolution and less blooming area than the conventional Doppler image. Dynamic Flow doesn't display THI, so the detectability of bubbles is superior to the other mode as far as Levovist. Dynamic Flow is so sensitive that it can show the bubbles in real time. Advanced Dynamic Flow(ADF) has greatly improved in sensitivity and presentation ability from conventional Dynamic Flow. In the contrast application, ADF image looks very similar to B-mode image thanks to the high resolution and wide dynamic range, in spite of using Doppler technique. Detectability of the bubbles is much better than conventional Dynamic Flow. ADF can detect bubbles in much smaller vessels and has much more penetration, with uniform enhancement from shallow to deep regions. ADF is very suitable for Levovist. ADF can also be used without contrast agents. ADF can show small tiny vessels with high resolution and high frame rate. Directional information can be added by different colors. The sensitivity is close to conventional Color/Power Doppler images.
Sato
Takeshi
T
Ultrasound Systems Development Department Medical Systems Company, Toshiba Corporation. takeshi.sato@toshiba.co.jp