Data from: Longitudinal characterization of local perfusion of the rat placenta using contrast-enhanced ultrasound imaging

The placenta provides a wide range of physiologic functions critical for
development. Insufficient placental perfusion resulting from improper
vascular remodeling is linked to many pregnancy-related diseases including
intrauterine growth restriction and preeclampsia. Here, we use
contrast-enhanced ultrasound (CEUS) to assess longitudinal, in vivo
placental perfusion through a pixel-wise time-intensity curve (TIC)
analysis. CEUS images were acquired of the placenta of pregnant Sprague
Dawley rats on gestational days (GD) 14, 16, and 18 after a bolus
injection of gas-filled microbubble contrast agents. Conventionally,
perfusion can be quantified using a TIC of contrast enhancement in an
averaged region of interest. However, the placenta has a complex structure
and flow profile, which is insufficiently described using the conventional
technique. In this work, we apply curve fitting in each pixel of the CEUS
image series in order to quantify hemodynamic parameters in the placenta
and surrounding tissue. We observed an increase in mean placental blood
volume and relative blood flow from GD14 to 18, while mean transit time of
the microbubbles decreased, demonstrating an overall rise in placental
perfusion during gestation. The variance of all three parameters increased
during gestation showing the regional differences in perfusion observable
using a pixel-wise TIC approach. Future work will use targeted microbubble
contrast agents to vascular remodeling in the placenta during pathologies
of pregnancy.