A Novel US method for the assessment of maternal, placental and fetal circulation during pregnancy

Doppler ultrasound (US) techniques are widely used in diagnostics to evaluate the maternal and fetal hemodynamics. Most of these studies involve the assessment of the blood flow in the fetal aorta, umbilical artery, and the uteroplacental circulation. The analysis is typically limited to the echoes originated from a sample volume (SV) covering the whole section of the vessel. Both the shape of the resulting sonogram and the corresponding quantitative indexes (e.g. PI, S/D and RI), have been proven to be relevant for diagnostic purposes and, in particular, to predict possible pregnancy complications. In this paper we propose the application of a method named multigate Spectral doppler analysis (MSDA), to improve the hemodynamic assessment in maternal and fetal circulation. In MSDA, the Doppler data from 128 SVs, aligned along an US scan line that intercepts the vessel, are independently analysed to produce high resolution velocity profiles. In the present study, the MSDA approach has been applied to 36 volunteers. Some example of flow profile extracted from maternal and fetal circulation is presented and the potentiality of the MSDA method to characterize the blood flow configurations is discussed