多普勒超声血流测量中仪器因素对速度测量影响的实验研究

目的　探讨不同彩色多普勒超声诊断仪对流速测定的可能影响 ,以及不同仪器测定流速与实际流速的差异和相关性。方法　利用体外模拟血流实验装置模拟 10种流速 ,在控制影响流速测定的主要因素的情况下 ,记录 5台不同类型的多普勒超声仪测定的流速。并使用其中 4台仪器测定 11名健康人的双侧颈总动脉收缩期峰值流速。比较多普勒测速与实际流速的相关性 ,以及不同仪器间流速测定的差异性。结果　体外模拟血流实验中多普勒测定的流速多数高于实际流速 ,但与实际流速之间有很好的相关性 (r=0 .96 4～ 0 .992 ,P<0 .0 0 0 5 )。 5台仪器的测定流速之间无显著性差异 ,但对流速大于 33.0 0 cm/s的数据进行分析可见其中 1台仪器与其他 4台仪器的测定流速两两之间存在显著性差异 (P<0 .0 5 )。进行人体颈总动脉的流速检测的 4台仪器中 ,该台仪器与其余 3台仪器的测速之间均有显著性差异 (P<0 .0 1)。结论　多普勒测量的流速与实际流速之间有很好的相关性 ,是评价血流动力学的有效手段。不同的多普勒超声仪器的流速测定可能存在一定差异 ,在评价正常或疾病情况下的血流速度时应当考虑到仪器因素 ,比较不同的研究结果应以已知测量的其他条件为前提。

Flow Measurements Using Doppler US:Experimental Study on Effects of Instrumentation in Velocity Evaluation

Objective To evaluate the probable effects of different instrumentation in velocity measurements and the correlations between the actual flow velocities and the Doppler flow velocity.Methods Ten different simulated velocities were tested by 5 different Doppler instruments on the in vitro flow phantom.Among the 5 instruments,4 were used to perform peak-velocity measurements in 11 normal persons' bilateral common carotid arteries(CCA).Statistics were conducted for these data as to define the correlations between the actual flow velocities and the Doppler flow velocities,and the velocity measurement discrepancy of different instruments. Results Most Doppler flow velocities exceeded the corresponding actual flow velocities,but significant correlations (r=0.964-0.992,P<0.000 5) exhibited between the actual flow velocities and the Doppler flow velocities.In the simulated flow experiments,no significant differences were found between any two instruments.However,a significant difference (P<0.05) was manifested between one instrument and each one of the other four instruments when the data of the actual velocity above 33.00 cm/s were analyzed respectively.Also,velocity measurements of this instrument showed significant differences (P<0.01) with those of the other three of the four when they were applied to the normal persons' CCAs.Conclusions The Doppler flow velocities and the actual flow velocities have significant correlations,which provides Doppler flow image as an effective method to evaluate hemodynamics.Different Doppler instruments may exist disparity on velocity measurements.When evaluating velocities of normal situition or diseases and referring to scientific articles,the instrumentation and calibration procedures should be considered.