Prenatal sonographic diagnosis of vasa previa: ultrasound findings and obstetric outcome in ten cases.

OBJECTIVE: To assess the specificity of sonographic diagnosis of vasa previa and pregnancy outcome in sonographically diagnosed cases. METHODS: We prospectively collected cases of vasa previa diagnosed by color Doppler sonography. Delivery by elective Cesarean section after demonstration of fetal pulmonary maturity and prior to the onset of labor was recommended unless obstetric complications supervened. Data regarding maternal obstetric courses and newborn status were collected. RESULTS: Eleven cases of vasa previa without placenta previa were diagnosed among 33 208 women over an 8-year period. Ten patients had confirmation of the diagnosis by the delivering obstetrician and/or placental examination, giving a specificity of diagnosis of 91%. Among the 10 patients with confirmed vasa previa, two were delivered at 31.5 and 35.5 weeks' gestation prior to demonstration of lung maturity, and the remainder were delivered at 34-37.5 weeks, after lung maturity. All infants had normal Apgar scores and survived. One baby had Scimitar syndrome, which was not suspected from sonography. CONCLUSIONS: The specificity of sonographic diagnosis of vasa previa at our center was 91%. Antenatal diagnosis permitted us to prevent the catastrophic outcomes commonly associated with vasa previa.     

A case of vasa previa diagnosed prenatally,and review of the literature

The perinatal mortality rate of vasa previa is high if it is not prenatally diagnosed. In this report, a case of vasa previa diagnosed prenatally is presented. Antepartum hemorrhage at 24 weeks of gestation prompted a close investigation of the uterine cervix, internal os, and placenta. We detected a low-lying bilobed placenta with umbilical cord insertion in the lower uterine segment. Furthermore, one of the connecting vessels of the bilobed placenta passed directly above the internal os. Vasa previa was suspected and confirmed with color Doppler and MRI. The fetus was delivered uneventfully by planned Cesarean section at 38 weeks of gestation. It should be considered that placenta previa (including low-lying placenta), bilobed placenta, and umbilical cord insertion in the lower uterine segment are associated with high risk of vasa previa. Ultrasound screening for cord insertion and placenta around the internal os enables efficient and certain detection of vasa previa.     

超声检查对胎儿脐带血管前置的诊断价值

目的 探讨彩色多普勒超声检查对胎儿脐带血管前置的诊断价值及其临床意义。 方法 回顾性分析2014年1月~2017年12月期间于我院产科进行产检并住院分娩后临床确诊为脐带血管前置的24例孕妇的彩色多普勒超声图像特点以及孕妇和胎儿结局。 结果 同期入院孕妇共8000例,前置血管发生率为0.3%。24例前置血管孕妇,彩色多普勒超声检查正确诊断出20例,正确率为83.33%,其中超声检查漏诊1例,漏诊率为4.17%,误诊3例,2例误诊为脐带先露,1例误诊为脐带脱垂。24例前置血管孕妇中14例为脐带血管帆状附着型,5例为副胎盘型,4例为双叶胎盘型,1例为脐带胎盘边缘附着型。24例诊断为前置血管的孕妇均接受剖宫产手术,其中活婴28个,死胎6个,孕妇均健康出院。 结论 产前超声检查能够直观显示孕妇子宫内脐带血管走形情况,并判断脐带血管与子宫颈内口的关系,在诊断前置血管上有较高的准确率,可作为前置血管筛查和诊断的首选检查手段,最终降低胎儿围产期死亡率。       

产前超声诊断血管前置的临床价值

目的 探讨产前超声检查诊断血管前置的临床价值。方法 回顾性分析接受产前超声检查的65 230例孕妇的超声声像图资料。统计产前超声诊断血管前置的准确率,随访血管前置产妇的分娩方式和围产儿结局。结果 产前超声初次检查拟诊血管前置53例,晚孕期复查排除10例,最终超声明确诊断43例。经临床证实41例（发生率41/65 230,0.06%）,其中中孕期（15~28周）筛查加晚孕期（28~40周）复诊诊断血管前置的准确率为100%（28/28）,仅行晚孕期检查诊断准确率为86.67%（13/15）。41例血管前置孕妇全部接受剖宫产手术,胎儿均存活。结论 产前超声诊断血管前置具有较高的临床应用价值。     

血管前置的产前超声诊断研究

目的 探讨血管前置产前超声诊断价值.方法回顾性分析38例妊娠合并血管前置孕妇产前超声声像图表现并追踪其妊娠结局.结果 产前超声共检出血管前置36例,漏诊2例,血管前置的产前超声检出率为94.7%(36/38),发生率为0.03%(38/141 568).产前超声检出的36例中,中孕期诊断30例(83.3%,30/36),晚孕期诊断6例(16.7%,6/36).经腹超声检查诊断的28例(77.8%,28/36),需进一步经会阴或经阴道超声检查的8例(22.8%,8/36).产前超声诊断的36例中,35例行择期剖宫产术生产并证实,无1例发生围产期死亡,1例因合并其他结构畸形引产处理.产前超声漏诊的2例均于阴道分娩时发生大出血并胎儿死亡.结论 中孕期是超声诊断血管前置的较佳时期.经腹超声检查是诊断血管前置的常规检查方法,对经腹超声检查宫颈内口不满意者,需行经会阴或经阴道超声检查排除血管前置.产前超声诊断血管前置并于临产前采取剖宫产处理能有效避免不良结局的发生.     

经腹部超声联合经阴道超声诊断血管前置的临床价值

目的探讨经腹部超声联合经阴道超声在产前诊断血管前置中的临床价值。 方法回顾性分析2018年1月至2019年12月在首都医科大学附属北京妇产医院因临床疑诊血管前置而行剖宫产手术的病例54例。以术后胎盘检查结果为"金标准"，对产前经腹部超声联合经阴道超声的检查结果进行分析，应用四格表计算得出其诊断血管前置的敏感度、特异度、阳性预测值、阴性预测值和准确性。 结果54例患者中，经腹部超声联合经阴道超声诊断血管前置47例，其中误诊3例，漏诊2例；5例因临床出血疑似诊断而手术，联合超声及术后证实均无血管前置。经腹部超声联合经阴道超声诊断血管前置的敏感度、特异度、阳性预测值、阴性预测值和准确性分别为95.7%（44/46）、62.5%（5/8）、93.6%（44/47）、71.4%（5/7）和90.1%（49/54）。 结论经腹部超声联合经阴道超声可为产前诊断血管前置提供更多的诊断信息和依据，减少干扰因素，具有良好的诊断效能，值得临床推广应用。     

Vasa previa: Prenatal diagnosis by transperineal sonography with Doppler evaluation

Antepartum diagnosis of vasa previa is of critical importance because of the high fetal mortality rate in unrecognized cases. This report describes the sonographic findings in 2 cases of vasa previa and demonstrates that transperineal sonography with Doppler evaluation can successfully establish the diagnosis of vasa previa prenatally. © 1998 John Wiley & Sons, Inc. J Clin Ultrasound 26:405–408, 1998.     

经腹联合经阴道超声诊断血管前置

目的 探讨经腹部超声(TAS)联合经阴道超声(TVS)检查诊断血管前置的临床应用价值。方法 回顾性分析31例产前临床疑诊血管前置孕妇的超声检查及手术病理资料。以手术病理结果为金标准,评价并比较单纯TAS检查与TAS联合TVS检查对血管前置的诊断效能。结果 21例经手术病理证实为血管前置,另10例非血管前置。单纯TAS检查的敏感度、特异度、准确率分别为80.95%(17/21)、63.64%(7/11)及77.42%(24/31);TAS联合TVS检查的敏感度(21/21)、特异度(10/10)及准确率(31/31)均为100%,均高于单纯TAS检查(P均< 0.05)。结论 TAS联合TVS检查诊断血管前置较单纯TAS检查可明显提高诊断敏感度、特异度及准确率。     

Prenatal diagnosis of an intertwin membrane hematoma

We report a case of a 26‐year‐old woman, gravida 2, para 1, with a dichorionic diamniotic twin pregnancy at 33 weeks of gestation with a 1‐day history of mild vaginal bleeding and irregular uterine activity. Ultrasonography showed 18 × 15 × 3‐cm‐sized complex hypoechoic mass located in the dividing intertwin membrane. Based on this finding, the diagnosis of an intertwin membrane hematoma was made. This unusual sonographic diagnosis was confirmed during the cesarean section. In the case of dichorionic twin pregnancy, partial placental abruption can lead to a subclinical intertwin membrane hematoma. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound 38:397‐399, 2010     

Three‐Dimensional Sonography of Placental Mesenchymal Dysplasia and Its Differential Diagnosis

Objective. Placental mesenchymal dysplasia (PMD) is an uncommon vascular anomaly of the placenta characterized by mesenchymal stem villous hyperplasia. Its main sonographic feature is a thickened placenta with hypoechoic areas, and an accurate sonographic diagnosis is challenging. The aim of this study was to report 2 cases of PMD and discuss the differential diagnosis of its sonographic features. Methods. Cases of placental masses were studied by 2‐dimensional (2D), 3‐dimensional (3D), and color Doppler imaging. Results. In case 1, a thick placenta with multiple hypoechoic areas was noted at 13 weeks' gestation. At 19 weeks, the multicystic area, clearly demarcated from a normal‐looking placenta, measured 6.5 × 8.5 cm and enlarged gradually. The patient gave birth to a 625‐g female neonate after spontaneous labor at almost 26 weeks' gestation. In case 2, a first sonographic examination at 25 weeks' gestation revealed a thickened placenta with hypoechoic areas and a fetus with a single umbilical artery and a ventricular septal defect. At 27 weeks, the abnormal area of the placenta measured 14.5 × 7.5 cm. At 32 weeks' gestation, a caesarean delivery was performed because of a nonreassuring fetal heart tracing, and a 1415‐g female neonate was delivered. Both cases were evaluated by 2D, 3D, and color Doppler imaging, and the pathologic features of both placentas were consistent with PMD. Conclusions. Placental mesenchymal dysplasia should be considered in the differential diagnosis of every placental mass, especially in cases of multicystic placental lesion with lack of high‐velocity signals inside the lesion, and a normal karyotype.     

Prenatal diagnosis of vertebral deformities associated with pentalogy of Cantrell: The role of three‐dimensional sonography?

Pentalogy of Cantrell was diagnosed in a fetus at 14 weeks of gestation, on routine two‐dimensional sonographic examination with Doppler imaging, which revealed a midline supraumbilical abdominal wall defect including herniated liver, an ectopia cordis without intracardiac anomalies, and a large omphalocele containing intestines. Although left unilateral club foot deformity was also detected as an associated anomaly in the same examination, severe lumbar lordoscoliosis was only detected by using three‐dimensional sonography because of the spatial configuration of the deformity. After termination of the pregnancy, postnatal inspection of the fetus confirmed the diagnosis of pentalogy of Cantrell associated with skeletal deformities and revealed low implant ears as an additional finding. Although two‐dimensional sonography with Doppler imaging is sufficient to diagnose pentalogy of Cantrell, it may fail to show the complex vertebral deformities and three‐dimensional sonography may assist in visualizing the defect accurately. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound 38:446–449, 2010     

Complete ectopia cordis with anencephaly: A case report

We report a case of pentalogy of Cantrell with anencephaly diagnosed in utero on 2‐dimensional sonography at 17 weeks of gestation. Due to associated anencephaly, termination of pregnancy was carried out. Histopathological examination confirmed the sonographic findings. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound, 2010     

Antenatal diagnosis of vasa previa by transvaginal color Doppler sonography.

Vasa previa is a rare complication of pregnancy with a high perinatal mortality, which has virtually not changed over the last 200 years. In this case report we describe the use of color Doppler ultrasonography to make a correct antepartum diagnosis of vasa previa. The baby was delivered by Cesarean section. A strategy is presented which may reduce the high mortality rate from this condition.     

Late pregnancy bleeding

Effective management of vaginal bleeding in late pregnancy requires recognition of potentially serious conditions, including placenta previa, placental abruption, and vasa previa. Placenta previa is commonly diagnosed on routine ultrasonography before 20 weeks' gestation, but in nearly 90 percent of patients it ultimately resolves. Women who have asymptomatic previa can continue normal activities, with repeat ultrasonographic evaluation at 28 weeks. Persistent previa in the third trimester mandates pelvic rest and hospitalization if significant bleeding occurs. Placental abruption is the most common cause of serious vaginal bleeding, occurring in 1 percent of pregnancies. Management of abruption may require rapid operative delivery to prevent neonatal morbidity and mortality. Vasa previa is rare but can result in fetal exsanguination with rupture of membranes. Significant vaginal bleeding from any cause is managed with rapid assessment of maternal and fetal status, fluid resuscitation, replacement of blood products when necessary, and an appropriately timed delivery.     

Placenta previa—is the traditional diagnostic approach satisfactory?

The accuracy of the diagnosis of placenta previa using transvaginal sonography (TVS) was compared to that of the traditional transabdominal sonography (TAS). Seventy seven women were scanned by both methods and each sonographic diagnosis was compared to the placental location at delivery. TVS was superior to TAS in diagnosing placenta previa and invariably correct in ruling it out. TVS (and TAS) failed to predict the placental location at delivery only in women diagnosed as having marginal placenta previa prior to 35 weeks gestation. The use of the vaginal probe significantly improved the accuracy of the diagnosis of placenta previa.     

Transvaginal ultrasonography in predicting placenta previa at delivery: a longitudinal study.

OBJECTIVES: To determine the extent of overlapping of the internal cervical os by the lower placental edge at 11-14 weeks' gestation which best predicts placenta previa at term. PATIENTS AND METHODS: This was a prospective study initially involving 381 singleton pregnancies with a live fetus at 11-14 weeks attending for routine antenatal care. The distance between the lower placental edge and the internal cervical os was longitudinally evaluated by transvaginal ultrasound examination at 11-14 weeks', 20-24 weeks', and 30-34 weeks' gestation. The first 203 cases were selected at random (first phase) and after this period only cases with the lower placental edge reaching and/or overlapping the internal cervical os were followed up (n = 170, second phase). Thus a total of 373 cases were analyzed, 351 of whom were examined in all three trimesters. Multiple regression analysis was used to estimate the probability of predicting placenta previa at term using the overlap of the lower placental edge over the internal cervical os in the first trimester of pregnancy. RESULTS: A change in the relative position of the placenta (placental migration) was observed in all 351 cases examined in the three trimesters of pregnancy. In the general population, represented by the 203 cases (first phase), the incidence of placenta previa at 11-14 weeks' gestation was 42.3% (86/203), at 20-24 weeks' 3.9% (8/203) and at term 1.9% (4/203). A total of 18 cases of placenta previa and 17 cases of marginal placenta were observed at term. It was estimated that when the lower placental edge overlaps the internal cervical os by 23 mm at 11-14 weeks the probability of placenta previa at term is 8% with a sensitivity of 83.3% and specificity of 86.1%. CONCLUSION: The present study establishes the probability of placenta previa at term depending on the relationship of the lower placental edge to the internal cervical os at 11-14 weeks.     

Vasa previa: A rare obstetric complication–A case series and a literature review

Vasa previa is a rare condition. However, since the increase in assisted reproductive technologies (ARTs), clinicians are more frequently confronted with this complication. In this study, we present five cases of vasa previa prenatally diagnosed from a tertiary referral hospital with approximately 2000 births yearly.     

Diagnosis of sirenomelia in the first trimester

Sirenomelia or “mermaid syndrome” is a rare congenital abnormality with an incidence of 1 in 60,000. We report a case diagnosed in the first trimester using two‐dimensional, three‐dimensional, and color Doppler ultrasound. With increasing emphasis on early diagnosis of fetal abnormalities, this case highlights the importance of looking for anomalies in the first trimester itself. In fact, the diagnosis of sirenomelia should be easier in the first trimester as severe oligohydramnios in later gestation hampers vision. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 42 :355–359, 2014