ROLE OF SHEAR WAVE ELASTOGRAPHY OF PLACENTA IN NORMAL AND PRE-ECLAMPTIC PREGNANCIES IN THIRD TRIMESTER

Abstract

INTRODUCTION Pre-eclampsia (PE) is a pregnancy-related condition characterized by new-onset hypertension (with systolic blood pressure > 140 mm Hg and diastolic blood pressure > 90 mm Hg on two occasions at least 4 hours apart, or more severe cases with higher values) along with proteinuria (elevated protein levels in urine). This condition resolves within the first 6 weeks after childbirth. This abnormal placental attachment and ineffective invasion of trophoblast cells into the muscular spiral arteries leads to hypoxia and placental ischemia. Shear wave elastography (SWE) is an innovative ultrasound technique designed to assess the elasticity of soft tissues. In the placenta, increased stiffness is a consequence of ischemia-related processes including inflammation, necrosis, infarction and fibrosis. The present study is planned to assess the utility of SWE in evaluation of placental function and can be used as a supplement to existing methods for prediction of PE. OBJECTIVES  To assess placental stiffness by shear wave elastography in third trimester.  To compare placental elastography findings in normal and pre- eclamptic pregnancies in third trimester. xviii MATERIAL AND METHODS This prospective case control study which includes 134 pregnant women in third trimester referred for obstetric scan on whom B-mode sonography and shear wave elastography was performed. Obstetric sonography and elastography of placenta will be performed using Philips EPIQ5 system equipped with shear wave point quantification, ELASTPQ, using curvilinear broadband transducer C5-1MHz. 67 women who had clinically normal pregnancies with normal fetal biometric measurements without any perinatal complications formed group A, and 67 women who had a clinical diagnosed preeclampsia formed group B. RESULTS Shear wave elastography values for case group 10.98 (9.70-13.13) were significantly higher than those for control group 2.90 (2.78-3.58) (P<0.001). No statistically significant difference was found between the elasticity values measured at the centre or edge of the placenta. CONCLUSION This study demonstrates that the use of shear wave elastography for detecting Placental stiffness has a good diagnostic performance for detecting Pre-Eclampsia. Shear wave elastography is a novel technique for characterizing tissues that is helpful for assessing tissue characterization, placental function and serves as an addition to current preeclampsia prediction tools.