Segmentation and volume quantification of villous tissue and
vessels
Images were pre-processed, analysed, and viewed withFIJI 26. Pre-processing consisted of de-noising
with a 3D median filter, sigma 1. Subsequently, placental villi
(autofluorescence), vessels, and SHG signal were segmented with the FIJI
Labkit plugin27.
Volume and surface areas of vessels and villi were quantified with3D ImageJ suite 28 (Figure S9, S10). Binary
images were imported into 3D ROImanager 28 to
obtain surface area and volume measurements. Villous vascular fraction
was calculated by dividing the vascular- and villous volume and
converted to percentage. The surface area to volume ratio (SA/Vol) was
quantified as a measure for effective diffusion area.