Villous Tree Model with Active Contractions for Estimating Blood Flow Conditions in the Human Placenta
Yoko Kato1, *, Michelle L. Oyen2, Graham J. Burton3
Identifiers and Pagination:Year: 2017
First Page: 36
Last Page: 48
Publisher Id: TOBEJ-11-36
Article History:Received Date: 30/10/2016
Revision Received Date: 12/01/2017
Acceptance Date: 17/02/2017
Electronic publication date: 14/04/2017
Collection year: 2017
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
In the human placenta, maternal and fetal bloods exchange substances through the surface of the villous trees: the fetal blood circulates in the villous trees, around which the maternal blood circulates. The blood flows directly influence fetal growth. Stem villi, the main supports of the villous tree, have contractile cells along the axes, whose contractions are expected to influence the blood circulations in the placenta. The displacement is neither measurable nor predictable while non-invasive measurements such as umbilical Doppler waveforms are helpful to predict the histological changes of the villous trees and vascularization in the placenta.
The displacement caused by the contraction of the villous tree is necessary to predict the blood flows in the placenta. Hence, a computational villous tree model, which actively contracts, was developed in this study.
The villous tree model was based on the previous reports: shear moduli of the human placenta; branching patterns in the stem villi. The displacement pattern in the placenta was estimated by the computational model when the shear elastic moduli were changed.
The results show that the displacement caused by the contraction was influenced by the shear elastic moduli, but kept useful for the blood flows in the placenta. The characteristics agreed with the robustness of the blood flows in the placenta.
The villous tree model, which actively contracts, was developed in this study. The combination of this computational model and non-invasive measurements will be useful to evaluate the condition of the placenta.