Preliminary study of acoustic radiation force impulse in the placental function of normal population and patients with severe preeclampsia / 中华超声影像学杂志

ABSTRACT

Objective To investigate the clinical value of acoustic radiation forcs impulse (ARFI)in quantitative evaluating placental elasticity.Methods The study population included 487 normal pregnant women,and ARFI generated shear wave velocity (SWV)was measured.On the basis of gestational ages, placental sites and sampling depths in region of interest (ROI),the normal population was divided into different groups.One-way analysis of variance was used to compare the discrepancy on the SWV values amomg the nomal placental sites or the sampling depths in ROI.Pearson correlation coefficient were used to assess the possible relationships between the normal placental SWV values and the different gestational ages or the placental grades.A total of 5 1 cases were diagnosed with severe preeclampsia,among them 25 cases were categorized as severe preeclampsia with fetal growth restriction (FGR).The placental SWV values were measured and compared with those of the normal population.The pathological examinations were performed on 50 normal and 5 1 abnormal placentas.Results Basing on the placental sites,the normal population were divided into three groupsanterior wall,lateral wall and posterior wall groups.Compared with the posterior wall group,the placental SWV values in the anterior wall or lateral wall group significantly decreased (P <0.05).No statistical significant difference was found between the anterior wall group and the lateral wall group.Basing on the distance from the sampling depths to the probe (range from 2 to 7.99 cm,and each additional 1 cm corresponding a group),the normal population were divided into six groups.There was statistical significant difference for the placental SWV values between the two groups of distance in the range of 2.0 to 5.99 cm and 6.0 to 7.99 cm (P <0.05).There was no statistical significant difference between the other two groups.The mean SWV value was (0.78±0.08 m/s)in the normal group. No significant relationships were found between the placental SWV values and the gestational ages of the normal population.However the placental SWV values were significantly related to the placental grades.For the placental SWV values,there was statistical significant difference between the normal group and the abnormal group (P <0.05).No statistical significant difference was found between the severe preeclampsia group and the severe preeclampsia with FGR group.The pathological examinations also showed significant changes in the abnormal group.Conclusions ARFI may quantitatively analyze the placental elasticity and make a difference between nomal and abnormal placenta.