Automated Visualization and Quantification of Spiral Artery Blood Flow Entering the First-Trimester Placenta, Using 3-D Power Doppler Ultrasound

Abstract

The goal of our research was to quantify the placental vascularity in 3-D at 11-13 + 6 wk of pregnancy at precise distances from the utero-placental interface (UPI) using 3-D power Doppler ultrasound. With this automated image analysis technique, differences in vascularity between normal and pathologic pregnancies may be observed. The algorithm was validated using a computer-generated image phantom and applied retrospectively in 143 patients. The following features from the PD data were recorded: The number of spiral artery jets into the inter-villous space, total geometric and PD area. These were automatically measured at discrete millimeter distances from the UPI. Differences in features were compared with pregnancy outcomes: Pre-eclamptic versus normal, all small-for-gestational age (SGA) to appropriate-for-gestational age (AGA) patients and AGA versus SGA in normotensives (Mann-Whitney). The Benjamini-Hochberg procedure was used (false discovery rate 10%) for multiple comparison testing. Features decreased with increasing distance from the UPI (Kruskal-Wallis test; p <0.001). At 2- 3 mm from the UPI, all features were smaller in pre-eclamptic compared with normal patients and for some in SGA compared with AGA patients (p <0.05). For AGA versus SGA in normotensive patients, no significant differences were found. Number of jets measured at 2-5 mm from the UPI did not vary because of the position of the placenta in the uterus (ANOVA; p > 0.05). This method provides a new in-vivo imaging tool for examining spiral artery development through pregnancy. Size and number of entrances of blood flow into the UPI could potentially be used to identify high-risk pregnancies and may provide a new imaging biomarker for placental insufficiency.

Contrast-Enhanced Ultrasound for the Assessment of Placental Development and Function

“…Abnormal Doppler indices are indicative of abnormal vascular resistance, providing some diagnostic utility for pregnancies at risk for placental insufficiency [ 9 , 10 ]. Doppler has also been implemented for more detailed assessments of the maternal blood flow to the spiral arteries [ 11 , 12 ] with advancements in modeling and quantification made using 3D power Doppler [ 13 , 14 ]. As an alternative, ultrasound contrast agents can be used to enhance the acoustic signal from blood in standard B-mode imaging resulting in improved grayscale enhancement [ 15 ].…”

Computational modeling of the interactions between the maternal and fetal circulations in human pregnancy

“…A new avenue for clinical ultrasound is the potential for the routine use of 3D ultrasound techniques as methodologies become faster, more robust, and less operator‐dependent (Roy‐Lacroix et al, 2017). Automated, or semi‐automated procedures to assess placental volume (Looney et al, 2018), as well as the vascularity of the uterus and placenta (Collins, Welsh, Impey, Noble, & Stevenson, 2017; Stevenson, Noble, Welsh, Impey, & Collins, 2018) provide opportunities for increased reliability in detecting pathological features in pregnancy. Computational modeling could aid development and interpretation of these evolving imaging tools by providing additional functional interpretation to features identified in ultrasound.…”

Advances in imaging feto-placental vasculature: new tools to elucidate the early life origins of health and disease

“…139 Moreover, 3D ultrasound has been used to reveal placental volume and vascularity. [140][141][142][143][144] These approaches provide not only the opportunity for a screening test for growth restriction but also novel insight into how placental vasculature informs future health outcomes.…”