Pitfalls in Ultrasound Diagnosis of Cesarean Scar Pregnancy

Abstract

Cesarean scar pregnancy (CSP) is a rare kind of ectopic pregnancy implanted in the previous cesarean scar and has an increasing incidence over the past 30 years. As the suspicion is low, the diagnosis may be delayed or misinterpreted in ultrasound, leading to treatment strategies that might end up in uterine rupture or hysterectomy. The objective here is to review the ultrasound findings in CSP with varied presentations. Transabdominal and transvaginal sonography combined with color Doppler is a reliable tool for the diagnosis of CSP. When the gestational sac is seen in lower part of the uterine cavity, differentiation between threatened miscarriage, cervical pregnancy and CSP could be difficult. Not all cases of CSP present with typical ultrasound findings and a high index of suspicion is needed for diagnosis in these cases. An attempted curettage or MTP pill taken in an undiagnosed CSP often alters the typical findings. The possibility of CSP should also be considered in cases presenting with abnormal uterine bleeding and have a prior history of cesarean section. With lack of awareness about this condition, the diagnosis can often be missed either with MRI or in ultrasound. Correct interpretation and timely diagnosis save the mother from life-threatening complications and also preserves future fertility.

The menace of caesarean scar pregnancy: a management challenge in modern obstetrics

“…Correct interpretation of findings can lead to better management and avoidance of life-threatening consequences. 14 The difficulty also arises in differentiating between and CSP and an inevitable abortion, though during last two decades ultrasound diagnosis has improved thanks to better machines and resolution. 15 Like the diagnosis, management of CSP is also not less challenging.…”

Tackling Caesarean Scar Pregnancy to Target Morbidly Adherent Placenta Previa– A Viable Option?

“…All cases of scar pregnancy, early and late placenta previa accrete in women with one or more previous caesarean were included in the study. The sono -imaging criteria used to diagnose scar pregnancy (9,10) was empty upper uterine cavity and cervical canal, with 1) the gestational sac with or without yolksac and /or fetal pole in the lower uterus corresponding to the scar area 2) Presence of a thinned out or ill-defined anterior myometrium adjacent to bladder with plenty of peri -trophoblastic flow 3) a heterogeneous vascular mass at the scar site in nonviable pregnancies Morbidly adherent placenta in the lower segment was diagnosed with ultrasound by any of the following features (11,12) 1) Loss of the normal retro placental sonolucent area 2) Intra -placental turbulent lacunae 3) Thinning or disruption of the hyper echogenic uterine serosa-bladder wall interface with vascularisation perpendicular to uterine wall. MRI was done when the ultrasound scan finding was doubtful.…”

Intrauterine ectopic pregnancy — ultrasound typing and treatment

“…In this study, the diagnosis of CSP and CP were based on ultrasound criteria reported on the literature [1,[7][8][9]12]. All cases were divided into two types according to the ultrasound presentation with a gestational sac (type I) or a heterogeneous mass (type II).…”

“…However, differentiating between CSP, CP, and threatened miscarriage via diagnostic ultrasound in a low-lying gestation sac is particularly difficult [8][9][10]. Not all cases of CSP and CP present with typical ultrasonic imaging [8]. Ectopic pregnancies are often accompanied by a hypoechoic mass in the lower uterine segment [11][12][13][14].…”

“…Ectopic pregnancies are often accompanied by a hypoechoic mass in the lower uterine segment [11][12][13][14]. Hypoechoic masses are atypical and are sometimes misdiagnosed as anterior myometrial fibroids or trophoblastic tumors [7,8]. At present, previous studies have mainly focused only on the gestational sac, and there is very little data on the hypoechoic mass on ultrasound findings as well as its proper management [11,15].…”