Nightingale K R, Trahey G E
Duke University Department of Biomedical Engineering, Durham, NC 27708, USA.
IEEE Trans Ultrason Ferroelectr Freq Control. 2000;47(1):201-14. doi: 10.1109/58.818763.
Streaming detection is an ultrasonic technique that can be used to distinguish fluid-filled lesions, or cysts, from solid lesions. With this technique, high intensity ultrasound pulses are used to induce acoustic streaming in cyst fluid, and this motion is detected using Doppler flow estimation methods. Results from a pilot clinical study were recently published in which acoustic streaming was successfully induced and detected in 14 of 15 simple breast cysts and four of 14 sonographically indeterminate breast lesions in vivo. In the study, the detected velocities were found to vary considerably among cysts and for different pulsing regimes. A finite element model of streaming detection is presented. This model is utilized to investigate methods of increasing induced acoustic streaming velocity while minimizing patient exposure to high intensity ultrasound during streaming detection. Parameters studied include intensity, frequency, acoustic beam shape, cyst-diameter, cyst fluid protein concentration, and cyst fluid viscosity. The model, which provides both transient and steady-state solutions, is shown to predict trends in streaming velocity accurately. Experimental results from studies investigating the potential for nonlinear streaming enhancement in cysts are also provided.
流动检测是一种超声技术，可用于区分充满液体的病变（即囊肿）和实性病变。利用该技术，高强度超声脉冲用于在囊肿液中诱导声流，然后使用多普勒血流估计方法检测这种运动。一项初步临床研究的结果最近发表，其中在15个单纯性乳腺囊肿中的14个以及14个超声检查不确定的乳腺病变中的4个中成功诱导并检测到了声流。在该研究中，发现检测到的速度在囊肿之间以及不同的脉冲模式下有很大差异。本文提出了一个流动检测的有限元模型。该模型用于研究在流动检测过程中增加诱导声流速度同时最小化患者对高强度超声暴露的方法。研究的参数包括强度、频率、声束形状、囊肿直径、囊肿液蛋白质浓度和囊肿液粘度。该模型提供瞬态和稳态解，结果表明其能准确预测声流速度的趋势。本文还提供了研究囊肿中非线性声流增强潜力的实验结果。
