Seidel G, Beller K D, Kaps M
Department of Neurology, Medical University at Lübeck, Germany.
Ultrasound Med Biol. 1996;22(8):1037-42. doi: 10.1016/s0301-5629(96)00127-5.
Ultrasound contrast agents (UCAs) are improving the signal-to-noise ratio of the reflected ultrasound so that Doppler frequency spectra can be recorded even under poor sonographic conditions. This is of particular diagnostic value in transcranial Doppler sonography. Depending on specific pharmacologic properties, echo-contrast agents may cause different increase and duration in Doppler signal amplitude. We used a dog model to study the temporal profile of Doppler signal amplitude after application of a phospholipid-containing echo-contrast agent (BY 963). In addition, we compared it with a contrast agent containing albumin (Albunex). Spherosome suspension BY 963 resulted in a dose-dependent increase in the duration of ultrasound amplification (Doppler enhancement of 1 mL, 3 mL and 10 mL of BY 963 per animal: 62.4 +/- 8.4, 72.8 +/- 9.2 and 67.7 +/- 4.2 s, respectively, n = 6). Detection of BY 963 in the extracranial jugular vein demonstrated that the UCA passes through the cerebral microcirculation (cerebral transit time was 2.2 +/- 0.2 s, n = 4). The signal enhancement lasted longer using the spherosome suspension compared with the albumin-containing solution (77.2 +/- 11.6 and 31.1 +/- 3.7 s, respectively, n = 6), and the maximum increase in intensity was more pronounced (27.0 +/- 2.0 and 17.5 +/- 2.2 dB, respectively, n = 6).
超声造影剂（UCAs）正在提高反射超声的信噪比，从而即使在超声检查条件较差的情况下也能记录多普勒频谱。这在经颅多普勒超声检查中具有特别的诊断价值。根据特定的药理特性，回声造影剂可能会导致多普勒信号幅度有不同程度的增加和持续时间。我们使用犬模型研究了应用含磷脂的回声造影剂（BY 963）后多普勒信号幅度的时间变化情况。此外，我们将其与含白蛋白的造影剂（Albunex）进行了比较。脂质体悬浮液BY 963导致超声增强持续时间呈剂量依赖性增加（每只动物给予1 mL、3 mL和10 mL BY 963时的多普勒增强分别为：62.4±8.4、72.8±9.2和67.7±4.2秒，n = 6）。在颅外颈静脉中检测到BY 963表明该超声造影剂可通过脑微循环（脑循环时间为2.2±0.2秒，n = 4）。与含白蛋白的溶液相比，使用脂质体悬浮液时信号增强持续时间更长（分别为77.2±11.6和31.1±3.7秒，n = 6），并且强度的最大增加更为明显（分别为27.0±2.0和17.5±2.2 dB，n = 6）。
