A Preliminary Study on the Safety of Elastography during Pregnancy: Hypoacusia, Anthropometry, and Apgar Score in Newborns

Virtual touch IQ elastography in the evaluation of fetal liver and placenta in pregnancies with gestational diabetes mellitus

OBJECTIVES

Elastography is considered a novel technique in the assessment of placenta parenchymal elasticity and very few data present the feasibility of elastography on human fetal tissue. This study aims to investigate the feasibility of fetal liver and placenta elastography and differences in pregnancies with GDM.

METHODS

Fifty-five women with GDM and 40 women with uncomplicated pregnancy as the control group was enrolled prospectively in this case-control study. Fetal liver VTIQ and placenta VTIQ elastography were performed between 25 and 39 weeks of pregnancy.

RESULTS

Mean placenta thickness at the level of umbilical cord insertion was significantly higher in the GDM group than in the control group (p=0.034). VTIQ elastography elasticity velocity (kPa) examinations revealed similar mean placenta and mean fetal liver stiffness in both groups. A weak to moderate correlation was observed between the mean elasticity of the placenta and the mean elasticity of the fetal liver (r=0.310; p=0.004).

CONCLUSIONS

Elastography may provide valuable information of especially on fetal tissue development and pathology. While placenta and fetal liver VTIQ elastography are feasible in pregnancy, the diagnostic value of these examinations in GDM is not certain and it seems to be that significant differences in SWE examinations that reflect structural changes in fetal tissue or placenta are more prominent in more chronic conditions such as type 1 and type 2 diabetes mellitus.

Value of shear-wave elastography and cerebral-placental-uterine ratio in women diagnosed with preeclampsia and fetal growth restriction in prediction of adverse perinatal outcomes

PURPOSE

The aim of this study was to measure placental stiffness with shear-wave elastography technique and to evaluate the relationship with cerebral-placental-uterine ratio (CPUR) and adverse perinatal outcomes in patient groups diagnosed with preeclampsia (PE) and fetal growth restriction (FGR) in the second and third trimesters compared to the control group.

MATERIALS AND METHODS

This prospective cross-sectional study was conducted at our hospital between March 2019 and March 2020. The study groups were divided into three groups: PE, FGR, and low risk pregnancy (LRP) group. The study population had singleton pregnancies and the placental site was at the anterior wall. Both shear-wave elasticity (SWE) and shear-wave velocity (SWV) were measured in the placenta during pregnancy. CPUR was calculated for each group.

RESULTS

A total of 147 patients were included in this study. The mean SWE (kilopascals) values in the PE group were significantly higher than in the FGR and controls (difference of means = 3.67, 9.45; 95% CI (1.23-6.1, 7-11.8); p < .05), respectively. The mean SWV values were significantly higher in PE and FGR groups than controls (p < .05). CPUR showed correlation with central maternal surface of placenta (p: .02, r: -0.184), central fetal surface of placenta (p < .001, r: -0.288), peripheral maternal surface of placenta (p: .002, r: -0.252), and peripheral fetal surface of placenta SWE values (p: .03, r: -0.181). NICU admission was correlated with central fetal surface of placenta SWE values (p: .002, r: 0.258).

CONCLUSION

In conclusion, we demonstrated increased placental stiffness in both the PE and the FGR group. Also, this difference was found to be more prominent in preeclampsia. This technique seems useful for assessment of placental function and may strengthen the utility of Doppler parameters for predicting adverse perinatal outcomes in high-risk pregnancies.

Prenatal quantification of human foetal lung and liver elasticities between 24 and 39 weeks of gestation using 2D shear wave elastography

Objectives

To quantify and model normal foetal lung and liver elasticities between 24 and 39 weeks of gestation (WG) using two-dimensional shear wave elastography (2D-SWE). To assess the impact of the distance between the probe and the target organ on the estimation of elasticity values.

Methods

Measurements of normal foetal lungs and liver elasticity were prospectively repeated monthly between 24 and 39 WG in 72 foetuses using 2D-SWE. Elasticity was quantified in the proximal lung and in the region inside the hepatic portal sinus. The distance between the probe and the target organ was recorded. Trajectories representing foetal lung and liver maturation from at least 3 measurements over time were modelled.

Results

The average elasticity for the lung and liver was significantly different from 24 WG to 36 WG (p < 0.01). Liver elasticity increased during gestation (3.86 kPa at 24 WG versus 4.45 kPa at 39 WG). From 24 WG to 32 WG, lung elasticity gradually increased (4.12kPa at 24 WG, 4.91kPa at 28 WG, 5.03kPa at 32 WG, p < 0.002). After 32 WG, lung elasticity decreased to 4.54kPa at 36 WG and 3.94kPa at 39 WG. The dispersion of the average elasticity values was greater for the lung than for the liver (p < 0.0001). Variation in the elasticity values was less important for the liver than for the lung. The values were considered valid and repeatable except for a probe-lung distance above 8cm.

Conclusion

Foetal lung and liver elasticities evolve differently through gestation. This could reflect the tissue maturation of both organs during gestation.

Trial registration

clinicaltrials.gov identifier: NCT03834805

Key Points

• Prenatal quantification of foetal lung elasticity using 2D shear wave elastography could be a new prenatal parameter for exploring foetal lung maturity.

• Liver elasticity increased progressively from 24 weeks of gestation (WG) to 39 WG, while lung elasticity increased first between 24 and 32 WG and then decreased after 32 WG.

• The values of elasticity are considered valid and repeatable except for a probe-lung distance above 8cm.