Subharmonic aided pressure estimation (SHAPE) is a technique that utilizes subharmonic signals from microbubble contrast agents for pressure estimation. Validation of the SHAPE technique relies on synchronous measurements of in vivo pressures using contrast microbubbles and a pressure catheter (reference standard). For the guidance and placement of pressure catheter in vivo, iodinated contrast is used with fluoroscopy. Therefore, during data acquisition for validation studies of the SHAPE technique, both contrast microbubbles and iodinated contrast are present simultaneously within the vasculature. This study aims to elucidate the effects of iodinated contrast (Visipaque, GE HealthCare) on subharmonic signal amplitude from contrast microbubbles (Definity, Lantheus Medical Imaging, Inc.). In an acrylic water tank, 0.06 mL of Definity and varied amounts of Visipaque (0.14, 0.43, 0.85, and 1.70 mL) were added to 425 mL of deionized water. Ultrasound scanning was performed with a SonixTablet scanner (BK Medical Systems) using optimized parameters for SHAPE with Definity ( ftransmit/receive = 3.0/1.5 MHz; chirp down pulse). Subharmonic data was acquired and analyzed at 9 different incident acoustic outputs ( n = 3). Results showed an increase in subharmonic signal amplitude from Definity microbubbles in the presence of 0.14 mL Visipaque by 2.8 ± 1.3 dB ( p < .001), no change with 0.85 mL Visipaque (0.7 ± 1.2 dB; p = .09) and a decrease in subharmonic amplitude in the presence of 1.70 mL Visipaque by 1.9 ± 0.7 dB ( p < .001). While statistically significant effect on subharmonic signal amplitude of Definity microbubbles was noted due to the mixture, the magnitude of the effect was minimal (~2.8 dB) and unlikely to impact in vivo SHAPE measurements.

中文翻译：

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混合碘造影剂和超声造影剂对次谐波信号的影响

次谐波辅助压力估计 (SHAPE) 是一种利用微泡造影剂的次谐波信号进行压力估计的技术。SHAPE 技术的验证依赖于使用对比微泡和压力导管（参考标准）同步测量体内压力。为了在体内引导和放置压力导管，碘造影剂与透视一起使用。因此，在 SHAPE 技术验证研究的数据采集过程中，造影微泡和碘造影剂同时存在于脉管系统内。本研究旨在阐明碘造影剂（Visipaque，GE HealthCare）对造影剂微泡（Definity，Lantheus Medical Imaging，Inc.）的次谐波信号幅度的影响。在丙烯酸​​水箱中，将 0.06 mL Definity 和不同量的 Visipaque（0.14、0.43、0.85 和 1.70 mL）添加到 425 mL 去离子水中。使用 SonixTablet 扫描仪（BK Medical Systems）使用优化的 SHAPE with Definity 参数进行超声扫描（ f发送/接收= 3.0/1.5 兆赫；啁啾下降脉冲）。在 9 个不同的事件声输出 (n = 3) 处采集和分析分谐波数据。结果显示，存在 0.14 mL Visipaque 时，Definity 微泡的次谐波信号幅度增加了 2.8 ± 1.3 dB (p < .001)，而 0.85 mL Visipaque 则没有变化 (0.7 ± 1.2 dB；p = .09)，并且降低了存在 1.70 mL Visipaque 时，分谐波幅度为 1.9 ± 0.7 dB (p < .001)。虽然混合物对 Definity 微泡的次谐波信号幅度产生了统计上显着的影响，但影响的幅度很小（约 2.8 dB），并且不太可能影响体内 SHAPE 测量。