Xie Fang, Wan Wen-Bo, Fei Xiang, Zhang Ming-Bo, Zhang Yan, Wang Hong-Wei, Tang Jie, Tang Wen-Bo, Luo Yu-Kun
Department of Ultrasound, Chinese PLA General Hospital, Beijing, China.
Braz J Med Biol Res. 2018;51(4):e7058. doi: 10.1590/1414-431x20177058. Epub 2018 Feb 26.
This study aimed to evaluate the feasibility and repeatability of the flash-replenishment method in contrast-enhanced ultrasound (CEUS) perfusion imaging and assess quantitatively microvascular perfusion in the liver. Twenty healthy New Zealand rabbits were submitted to CEUS perfusion imaging with continuous intravenous infusion. Using flash-replenishment kinetics, the dynamic process of depletion and refilling of microbubble contrast agent was recorded. The hepatic microvascular perfusion parameters were calculated, including region of interest, peak intensity (PI), area under the curve (AUC), and hepatic artery to vein transit time (HA-HVTT). A consistency test was performed for multiple measurements by the same operator and blind measurements by two different operators. The hepatic perfusion imaging of 3×108 bubbles/min had minimal error and the best imaging effect and repeatability. The variability of the perfusion parameter measured at 3 cm depth under the liver capsule was at a minimum with coefficient of variation of 3.9%. The interclass correlation coefficient (ICC) of measurements taken by the same operator was 0.985, (95% confidence interval, CI=0.927-0.998). Measurements taken by two operators had good consistency and reliability, with the ICC of 0.948 (95%CI=0.853-0.982). The PI and AUC of liver parenchyma after reperfusion were lower than before blocking; and HA-HVTT was significantly longer than before blocking (P<0.05). The flash-replenishment method in CEUS perfusion imaging showed good stability and repeatability, which provide a valuable experimental basis for the quantitative assessment of hepatic microvascular perfusion in clinical practice.
本研究旨在评估超声造影（CEUS）灌注成像中快速补充法的可行性和可重复性，并定量评估肝脏微血管灌注。对20只健康的新西兰兔进行连续静脉输注的CEUS灌注成像。采用快速补充动力学，记录微泡造影剂的消耗和再充盈动态过程。计算肝脏微血管灌注参数，包括感兴趣区、峰值强度（PI）、曲线下面积（AUC）和肝动脉至静脉渡越时间（HA-HVTT）。由同一操作者进行多次测量以及由两名不同操作者进行盲法测量，并进行一致性检验。3×108个气泡/分钟的肝脏灌注成像误差最小，成像效果和可重复性最佳。肝包膜下3 cm深度处测量的灌注参数变异性最小，变异系数为3.9%。同一操作者测量的组内相关系数（ICC）为0.985（95%置信区间，CI = 0.927 - 0.998）。两名操作者测量结果具有良好的一致性和可靠性，ICC为0.948（95%CI = 0.853 - 0.982）。再灌注后肝实质的PI和AUC低于阻断前；且HA-HVTT显著长于阻断前（P<0.05）。CEUS灌注成像中的快速补充法显示出良好的稳定性和可重复性，为临床实践中肝脏微血管灌注的定量评估提供了有价值的实验依据。
