Claassen L, Seidel G, Algermissen C
Department of Neurology, Medical University Lübeck, Lübeck, Germany.
Ultrasound Med Biol. 2001 Jan;27(1):83-8. doi: 10.1016/s0301-5629(00)00324-0.
It is unclear if the dye-dilution theory and its corresponding parameters are capable of measuring brain perfusion using harmonic grey-scale imaging. We performed a study on a flow phantom using a SONOS 5500 (1.8--3.6-MHz harmonic imaging) and Levovist as the ultrasound (US) contrast agent (UCA). We applied the UCA in six different doses (0.1 to 3.0 mL) and used eight different flow-rates (180 to 540 mL/min). Additionally, we performed a study on dog brain using Levovist boluses of 1.5 mL and 3 mL. We evaluated the influence of dose and flow-rate on the parameters of the time-intensity curve: peak signal intensity (PSI), area under the curve (AUC) and mean transit time (MTT). Along with an increase of the Levovist dose, the AUC and the PSI increased only in the dose range between 0.1 and 0.5 mL Levovist; further increase led to no change of parameters. Flow-rate showed no influence on AUC, MTT or PSI. The dye-dilution theory is not a useful theoretical model for the analysis of perfusion using harmonic grey-scale imaging. A possible explanation for this effect is the bubble saturation.
尚不清楚染料稀释理论及其相应参数是否能够使用谐波灰阶成像测量脑灌注。我们使用SONOS 5500（1.8 - 3.6兆赫谐波成像）和Levovist作为超声（US）造影剂（UCA）对流动模型进行了一项研究。我们应用了六种不同剂量（0.1至3.0毫升）的UCA，并使用了八种不同的流速（180至540毫升/分钟）。此外，我们使用1.5毫升和3毫升的Levovist团注对犬脑进行了一项研究。我们评估了剂量和流速对时间强度曲线参数的影响：峰值信号强度（PSI）、曲线下面积（AUC）和平均通过时间（MTT）。随着Levovist剂量的增加，AUC和PSI仅在0.1至0.5毫升Levovist的剂量范围内增加；进一步增加导致参数没有变化。流速对AUC、MTT或PSI没有影响。染料稀释理论不是用于谐波灰阶成像灌注分析的有用理论模型。对此效应的一个可能解释是气泡饱和。
