肝脏超声造影定量分析中的影响因素

Impact factors in the quantitative analysis of liver contrast-enhanced ultrasonography

目的探讨不同因素对肝脏超声造影时间-强度曲线(TIC)的影响。方法选取健康志愿者7名,经左侧肘静脉以6种不同剂量注射造影剂,采用QLab软件描绘TIC获取每一剂量在不同监测条件下的常用血流灌注参数。结果①相同面积和形状ROI:随深度增加,增强强度(ΔI)明显减低。②在低剂量时(0.5 ml和1.0 ml),ΔI随剂量增加而增加;但剂量增大后,ΔI无明显差别。③改变面积和形状,不同ROI之间ΔI差异无统计学意义(P>0.05)。④聚焦深度增加,ΔI呈现下降趋势。⑤ΔI和上升时间(Δt)的比值(ΔI/Δt)与造影剂剂量之间无明显相关性。结论造影剂剂量对造影参数的影响较大,而改变ROI的大小和形状对造影参数无显著影响;于适当位置选取ROI才能获得理想的造影参数,聚焦位置不同可以影响造影剂微泡的稳定性,从而对造影效果产生影响。

Objective To explore the impact factors of time-intensity curve（TIC） in the liver CEUS.Methods Contrast agent in six-doses were injected to 7 healthy volunteers,then common perfusion parameters were acquired from TIC.Results ①Keeping ROI in the same shape and area,the intensity（ΔI） decreased with the depth increased.②In the lower dose（0.5 ml and 1.0 ml）,ΔI increased with the dose elevated.③When the shape and area of ROI changed,no statistically different of ΔI was found（P0.05）.④ΔI decreased with the deeper focus.⑤ΔI/rise time did not significantly correlated with doses.Conclusion The contrast paremeters are significantly influenced by dose of contrast agent.With the changing of shape and area of ROI,the contrast parameters change scarcely.ROI should be put at proper depth to get satisfactory parameters.The position of the focus has effects on the stability of the microbubbles,therefore influences the results of CEUS.