Figure 2.
Broadband imaging achieves higher resolution than multi-pulse imaging in less time with equal sensitivity. Comparative performance of broadband (T2R15) and multi-pulse (CPS) imaging in vitro. A, B: Microbubbles flowing through two 200 μm-diameter tubes, separated by 400 μm, were imaged by (A) broadband (T2R15) imaging and (B) multi-pulse (CPS) imaging mode. Both images have a 40-dB dynamic range and consist of 512 scan lines. The vertical scale bar in (A) and (B) represents 2 mm. C: Broadband (T2R15) echo from a single circulating (left) and bound microbubble (right). D: Multi-pulse signals (CPS, post-summation) from a single circulating (left) and bound (right) microbubble. E: For echoes received from the same bound microbubble, the echo amplitude was greater for broadband excitation and (F) the root mean squared integral of the echo amplitude received from a single microbubble by the 15 MHz and 2.25 MHz transducers was similar. The transmitted pressure was 250 kPa for (C-F).