Assessment of placental blood flow between 22 and 34 weeks of gestation by 3D-sonography power Doppler vascular indices.

PURPOSE

To analyze and compare the vascular flow in different parts of the placenta of normal pregnant women between 22 and 34 weeks of gestation through three-dimensional power Doppler ultrasonography (3D power Doppler) vascular indices.

METHODS

This is a cross-sectional study involving 55 normal pregnant women with gestational ages between 22 and 34 weeks. The vascularization index (VI), flow index (FI) and vascularization flow index (VFI) were obtained using the virtual organ computer-aided analysis (VOCAL) method both in the region of placental cord insertion and the peripheral region of the placenta. The Wilcoxon test was applied, adopting a significance level of 5% to evaluate possible differences in these indices between study areas.

RESULTS

For the three indices examined (VI, FI and VFI), a statistically significant difference was obtained between the insertion of the umbilical cord, designated as the center, and the placental periphery on both the right (p < 0.001 for VI, p = 0.001 for FI and p < 0.001 for VFI) and the left (p < 0.001 for VI, p < 0.001 for FI and p = 0.001 for VFI), taken as the average of the rates obtained in the two peripheries (p < 0.001 for VI, p < 0.001 for FI and p = 0.003 for VFI). Differences were not found when the two peripheral areas were compared or if placenta was anterior or posterior (p > 0.05).

CONCLUSION

There is a statistically significant difference between the vascular indices obtained with a 3D power Doppler at different points of the placenta.