Features of ultrasound diagnosis of pathological placentation

Abstract

Pathological placentation (placenta previa and placenta accreta) is one of the main problems in modern obstetrics, which negatively affects maternal and perinatal mortality rates. The use of modern technologies for the timely diagnosis of this pregnancy complication and the correct route of the patient allow to reduce blood loss significantly, to save not only the life of the mother and the child, but also to save the uterus in some cases.The objective: to evaluate the diagnostic possibilities of ultrasound examination of pathological placentation.Materials and methods. An ultrasound examination was performed in 86 pregnant women with pathological placentation. Ultrasound signs of pathological placentation are divided into two groups depending on the gray or color image.Results. In 92 % of examined pregnant women with pathological placentation, the clear zone was lost. In patients with placenta previa a loss of the hypoechoic retroplacental zone was found in 70 % of cases, a significant number of placental lacunae of various shapes and sizes – 87 %, segmental thinning of the myometrium <1 mm – 50 %.Protrusion of the uterus into the surrounding tissues is often observed due to placenta accreta, in cases of placenta percreta – the exophytic mass indicates the invasion of the placental tissue through the myometrium into the extrauterine organs. 80 % of pregnant women with placenta previa and 75 % of patients with placenta accreta have hypervascularization within or under the placental bed.Conclusions. Ultrasound examination is an affordable and effective method of visualization of pathological placentation. The following criteria for placenta accreta were established and confirmed: myometrial thinning <1 mm, placental lacunae, bladder wall rupture, loss of the lunate zone, placental protrusion, subplacental vascularization, uterovesicular hypervascularization, and vessels that vascularize the lacunae.