Arch Gynecol Obstet (2011) 284:53–57 DOI 10.1007/s00404-010-1595-x 123 MATERNO-FETAL MEDICINE Assessment of placental blood Xow between 22 and 34 weeks of gestation by 3D-sonography power Doppler vascular indices Rômulo Negrini · Luiz Cláudio de Silva Bussamra · Leonardo da Silva Valladão de Freitas · Edward Araujo Júnior · Sebastião Piato · Luciano Marcondes Machado Nardozza · Antonio Fernandes Moron · Tsutomu Aoki Received: 22 April 2010 / Accepted: 6 July 2010 / Published online: 22 July 2010  Springer-Verlag 2010 Abstract Purpose To analyze and compare the vascular Xow in diVerent parts of the placenta of normal pregnant women between 22 and 34 weeks of gestation through three-dimen- sional power Doppler ultrasonography (3D power Doppler) vascular indices. Methods This is a cross-sectional study involving 55 nor- mal pregnant women with gestational ages between 22 and 34 weeks. The vascularization index (VI), Xow index (FI) and vascularization Xow 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 signiWcance level of 5% to evaluate possible diVerences in these indices between study areas. Results For the three indices examined (VI, FI and VFI), a statistically signiWcant diVerence 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). DiVerences 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 signiWcant diVerence between the vascular indices obtained with a 3D power Doppler at diVerent points of the placenta. Keywords Placental · Normal pregnancies · Vascular indices · Three-dimensional power Doppler ultrasonography Introduction The advent of the power Doppler technology in the 1980s with the objective of evaluating valvular regurgitation from the heart did not bring beneWts compared to conventional Doppler [1, 2]. However, the same technology was reintro- duced in 1994 by Rubin et al. with the objective of evaluat- ing blood vessels of small arms, in which function was superior, especially when associated with the tridimen- sional technology [3, 4]. Since then, a series of studies was started in diVerent Welds of medicine and more recently in the evaluation of placental blood Xow, the analysis of the microvascularization of which was only possible through anatomical–pathological methods [5–7]. It did not take long to consider the possibility of a quan- titative vascular analysis of the region observed. This was analyzed through the vascular indices as VI (vasculariza- tion index), FI (Xow index) and VFI (vascularization Xow index), which show the quantity of vessels, the local blood Xow and their combination [8]. Parleitner et al. [8] consid- ered that the pre-determined area was formed of small pieces of volume named voxels. From then on, they were divided into gray voxels, pieces that compose the noncol- R. Negrini · L. C. de Silva Bussamra · L. da Silva Valladão de Freitas · T. Aoki Department of Obstetrics and Gynecology, Medical Science College of Santa Casa of São Paulo (FCMSCSP), São Paulo, SP, Brazil L. C. de Silva Bussamra · E. Araujo Júnior (&) · S. Piato · L. M. M. Nardozza · A. F. Moron Department of Obstetrics, São Paulo Federal University (UNIFESP), Rua Carlos Weber, 950 Apto, 113 Visage, Alto da Lapa, São Paulo, SP 05303-000, Brazil e-mail: araujojred@terra.com.br