The middle cerebral artery peak systolic velocity (MCA- PSV) has been successfully used for timing the first 2 transfusions in fetuses at risk for anemia because of maternal red cell alloimmunization. The Abstract of ...The middle cerebral artery peak systolic velocity (MCA- PSV) has been successfully used for timing the first 2 transfusions in fetuses at risk for anemia because of maternal red cell alloimmunization. The Abstract of this study was to assess whether the correlation between the MCA- PSV and fetal hemoglobin is maintained in fetuses that had undergone 2 previous intrauterine transfusions. Study design: Doppler measurement of MCA- PSV was performed before cordocentesis in 39 fetuses. The timing of the third transfusion was based on traditional criteria. The values of MCA- PSV and hemoglobin were expressed as multiples of the median (MoM). Anemia was defined as mild (hemoglobin < 0.84 MoM for a given gestational age, moderate (hemoglobin < 0.65 MoM), and severe (hemoglobin < 0.55 MoM). Regression analysis was used to assess the correlation between the MCA- PSV MoM and fetal hemoglobin MoM. Results: Gestational age at Doppler study ranged from 22 to 35 weeks. Six fetuses (15% ) had normal hemoglobin concentration; 21 (53% ) had mild anemia; 7 (20% ) had moderate anemia; and 5 (12% ) had severe anemia. There was a linear correlation between fetal hemoglobin (y) and the MCA- PSV (x): y = 1.185 - 0.341x. Conclusion: Previously, concerns have been expressed about the accuracy of Doppler prediction of anemia after previous transfusions. Our data suggest that there is a good correlation between the MCA- PSV and fetal hemoglobin in fetuses that have undergone 2 previous transfusions. Our findings expand the clinical situation in which Doppler can be used to monitor red cell alloimmunized pregnancies.展开更多
目的通过对比观察不同角度的楔形导声垫在颈动脉超声检查中获得的参数,探讨楔形导声垫在血管超声检查中的应用价值。方法对50例颈动脉超声检查结果阴性的成人患者右侧颈总动脉进行超声检查,在无导声垫及使用18°、25°、32°...目的通过对比观察不同角度的楔形导声垫在颈动脉超声检查中获得的参数,探讨楔形导声垫在血管超声检查中的应用价值。方法对50例颈动脉超声检查结果阴性的成人患者右侧颈总动脉进行超声检查,在无导声垫及使用18°、25°、32°楔形导声垫四种条件下测量颈总动脉收缩期峰值流速(Peak systolic velocity,PSV,cm/s)及多普勒角度。结果无导声垫及使用18°、25°、32°楔形导声垫,测得的颈总动脉PSV分别为(90.10±8.21)cm/s、(84.42±7.91)cm/s、(78.30±7.88)cm/s、(72.25±7.62)cm/s,差异均有统计学意义,P值均<0.01,变异系数(Coefficient of Variation,CV)分别为0.091、0.094、0.100、0.101;多普勒角度校正分别为(59.78±0.51)°、(54.92±1.51)°、(50.78±2.48)°、(46.22±2.82)°,差异均有统计学意义,P值均<0.01,CV分别为0.008、0.027、0.049、0.061。结论增加楔形导声垫角度可明显降低颈动脉血流速PSV及多普勒角度,潜在提高了超声评估颈动脉血流速度的准确性,对PSV的变异系数影响不明显。展开更多
文摘The middle cerebral artery peak systolic velocity (MCA- PSV) has been successfully used for timing the first 2 transfusions in fetuses at risk for anemia because of maternal red cell alloimmunization. The Abstract of this study was to assess whether the correlation between the MCA- PSV and fetal hemoglobin is maintained in fetuses that had undergone 2 previous intrauterine transfusions. Study design: Doppler measurement of MCA- PSV was performed before cordocentesis in 39 fetuses. The timing of the third transfusion was based on traditional criteria. The values of MCA- PSV and hemoglobin were expressed as multiples of the median (MoM). Anemia was defined as mild (hemoglobin < 0.84 MoM for a given gestational age, moderate (hemoglobin < 0.65 MoM), and severe (hemoglobin < 0.55 MoM). Regression analysis was used to assess the correlation between the MCA- PSV MoM and fetal hemoglobin MoM. Results: Gestational age at Doppler study ranged from 22 to 35 weeks. Six fetuses (15% ) had normal hemoglobin concentration; 21 (53% ) had mild anemia; 7 (20% ) had moderate anemia; and 5 (12% ) had severe anemia. There was a linear correlation between fetal hemoglobin (y) and the MCA- PSV (x): y = 1.185 - 0.341x. Conclusion: Previously, concerns have been expressed about the accuracy of Doppler prediction of anemia after previous transfusions. Our data suggest that there is a good correlation between the MCA- PSV and fetal hemoglobin in fetuses that have undergone 2 previous transfusions. Our findings expand the clinical situation in which Doppler can be used to monitor red cell alloimmunized pregnancies.
文摘目的通过对比观察不同角度的楔形导声垫在颈动脉超声检查中获得的参数,探讨楔形导声垫在血管超声检查中的应用价值。方法对50例颈动脉超声检查结果阴性的成人患者右侧颈总动脉进行超声检查,在无导声垫及使用18°、25°、32°楔形导声垫四种条件下测量颈总动脉收缩期峰值流速(Peak systolic velocity,PSV,cm/s)及多普勒角度。结果无导声垫及使用18°、25°、32°楔形导声垫,测得的颈总动脉PSV分别为(90.10±8.21)cm/s、(84.42±7.91)cm/s、(78.30±7.88)cm/s、(72.25±7.62)cm/s,差异均有统计学意义,P值均<0.01,变异系数(Coefficient of Variation,CV)分别为0.091、0.094、0.100、0.101;多普勒角度校正分别为(59.78±0.51)°、(54.92±1.51)°、(50.78±2.48)°、(46.22±2.82)°,差异均有统计学意义,P值均<0.01,CV分别为0.008、0.027、0.049、0.061。结论增加楔形导声垫角度可明显降低颈动脉血流速PSV及多普勒角度,潜在提高了超声评估颈动脉血流速度的准确性,对PSV的变异系数影响不明显。
