Laboratory measurement of placenta stiffness as reference method for shear wave elastography. a pilot study

* Kharchenko M, ** Dynnyk O.B., *** Miskovic B.
* Department of Obstetrics and Gynecology, Health Center Ozalj, Ozalj, Croatia
** Department of Clinical Pathophysiology, A.A.Bogomolets Institute of Physiology,
National Academy of Science, Ukraine
*** Department of Obstetrics and Gynecology, School of Medicine, University of Zagreb,
Sveti Duh Clinical Hospital, Zagreb, Croatia

Introduction. Shear wave elastography (SWE) is ultrasound-based technique used in clinical practice since 2009 and allows to quantify the stiffness of soft tissues. The stiffness of tissues varies considerably in normal and pathology.

The aim of the study was to compare the Young's elasticity modulus of placental tissue, obtained during ultrasound examination of placenta in vivo and in vitro using shear wave elastography mode, with dynamometry data in vitro.

Materials and Methods. Measurement of placental tissue elasticity modulus in vivo was carried on pregnant women in the first stage of labor between contractions, with ultrasound machine «Ultima SE» produced by company Radmir (Ukraine), using SWE mode and 2-5 MHz probe. We were evaluating average values of Young's modulus in central and peripheral regions of placentas. In vitro placental tissue was examined immediately after birth, initially by 2-10 MHz probe using SWE, and then in laboratory, measuring stiffness of central and peripheral regions with dynamometer and calculating average value of Young's modulus. The study included only healthy women with normal delivery and anamnestic normal pregnancy.

Results. Young’s elasticity modulus measured by SWE (M ± SD) are summarized in Table 1. Statistically insignificant increase of values of Young's modulus in vitro compared to values in vivo can be explained by changes in the mechanical properties of biological tissues after death and by inability to completely avoid compression by the ultrasonic transducer during inspection.

Table 1. Values of Young’s Elasticity Modulus


Young’s Elasticity Modulus, kPa

SWE in vivo

SWE in vitro

Dynamometry in vitro

Central region

5,93 ±1,58

9,25 ±0,98

8,32 ±1,30

Peripheral regions

6,14 ± 1,22

9,43 ± 1,41

9,24 ±1,28


Conclusions. During comparison of average values of elasticity modulus of placental tissue obtained in vivo and in vitro by SWE and by laboratory measurements, statistically significant deviations were not observed.