评价颈动脉功能新参数的临床应用价值探讨

目的 应用超声射频信号血管内中膜分析(quality intima-media thickness,QIMT)技术探讨正常人冷加压试验前后颈总动脉内径百分变化率(D%)与颈总动脉血流平均波强和波强距离比参数评价颈总动脉功能的可行性.方法 应用QIMT技术观察24例健康志愿者静息状态下,冷加压负荷试验后的左侧颈总动脉,测量其收缩末期、舒张末期内径及颈总动脉血流参数,并计算内径变化范围、百分变化率、血流平均波强和波强距离比.绘制血管内径百分变化率、血流平均波强和波强距离比的受试者工作特征(ROC)曲线,比较三者的检验效能.结果 与试验前相比,正常人颈总动脉内径变化幅度与内径百分变化率均显著减低,血流平均波强与波强距离比显著增加,差异有统计学意义(P<0.05).波强距离比,平均波强和内径百分变化ROC曲线下面积分别为0.827、0.821和0.728,三者间差异无统计学意义(P>0.05).结论 QIMT可准确测量冷加压前后颈总动脉内径百分变化率,可通过常规血流动力学参数计算血流平均波强、波强距离比评价颈总动脉功能.

Significance of new parameters in evaluation the function of carotid artery

Objective To evaluate the parameters of inner diameter different rate (D%), mean wave intensity(MWl) and diameter-adjusted mean wave intension(DAMWI) in assessing the function of common carotid artery(CCA) by quality intima-media thickness(QIMT) technique. Methods Twenty-four healthy subjects were performed 2D and CDFI examination under the normal quiescent and cold pressor test(CPT) condition respectively. The diastolic and systolic diameters of left-CCA were measured by QIMT respectively. Corresponding the inner diameter different range,rate,MWI and DAMWI were calculated respectively. The curves of their ROC were drawn. Results The different range and rate of diameters were decreased when subjects suffered CPT (P< 0.05) ,but the MWI and DAMWI were increased (P<0. 05). The areas under the ROC curves were 0. 827,0. 821 and 0.728 corresponding DAMWI, MWl and different rate of diameter. There was no significant difference among them(P>0. 05). Conclusions Conclusions The changed rate of diameter can be measured exactly by QIMT. The function of CCA can Be evaluated by MW1 and DAMWI which were calculated by conventional parameters.