Differential diagnosis of paracervical vascular anomalies in pregnancy

Abstract

In this article, we illustrate the ultrasound characteristics of paracervical vascular anomalies during pregnancy and the puerperium, focusing on the presence of voluminous venous varices along the course of the uterine vessels and on pseudoaneurysms of the uterine artery (UAP). These anomalies, one of venous and one of arterial origin, may share some common ultrasound features, but have completely different prognoses in pregnancy and different risk of rupture, so their differential diagnosis is crucial for management.UAP is a rare cause of bleeding in pregnancy, with three cases in every 1000 pregnancies 1 . Its occurrence is a possible life-threatening event both for mother and fetus. UAPs are usually the result of vascular damage incurred during gynecological surgery, both laparotomic and laparoscopic, such as myomectomy, hysterectomy, endometriosis surgery and Cesarean section, particularly when performed during labor 2 . UAPs can also occur spontaneously during pregnancy or after uncomplicated delivery. In our experience, endometriosis, and in particular deep endometriosis, is a risk factor for vascular dilatation due to chronic local inflammation, adhesions (even in the absence of previous surgical intervention 3 ) and decidualization of lesions during pregnancy, making tissues more fragile. Unlike true aneurysm, in which all three layers of the arterial wall are dilated, UAP is characterized by damage to the tunica intima, with turbulent blood flow filling the space between tunica media and adventitia and communicating with the lumen of the feeding artery. UAPs can be asymptomatic, with incidental diagnosis during routine ultrasound; otherwise, symptoms are aspecific, such as pelvic pain, fever or vaginal bleeding. However, in the case of rupture, UAPs can cause hemorrhagic shock and severe pain. In non-pregnant women, the risk of rupture is considered to be high if the diameter of the UAP exceeds 2 cm. Little is known about the risk of rupture during pregnancy, but it is likely to be increased further by hyperdynamic circulation, especially during the third trimester. The diagnosis is made using ultrasound, both transvaginal and transabdominal, based on the observa-