178例颈项透明层增厚胎儿的围产结局

目的 探讨妊娠早期颈项透明层(nuchal translucency,NT)增厚胎儿的妊娠结局.方法 以相同顶臀径胎儿的NT值的第95百分位数作为NT增厚的标准,对2008年1月至2009年12月在广州市妇女儿童医疗中心产前诊断为妊娠早期单胎胎儿NT增厚的孕妇行回顾性随访.随访内容主要包括产前检查情况及新生儿出生后健康状况,新生儿随访至出生后至少3个月.采用单因素方差分析和多重比较方法分析不同NT值与胎儿围产结局的关系.结果 178例NT增厚病例中,2例自然流产,19例终止妊娠(21-三体6例、重型α地中海贫血5例、超声发现胎儿畸形7例和1例社会原因),157例分娩新生儿中,1例出生后发现先天性心脏病.总体胎儿异常率为11.8％(21/178),胎儿异常检出率为95.2％(20/21).NT在第95百分位数和2.9 mm之间者的胎儿健康存活率为96.1％(122/127);NT为3.0～3.9 mm者的胎儿健康存活比例为82.4％(28/34);NT≥4.0 mm者的胎儿健康存活比例为35.3％ (6/17)(F=29.08,P＜0.001).结论 NT增厚与不良妊娠结局密切相关,随着NT增厚程度的增加,胎儿健康存活率显著降低.当NT≥4.0 mm时,胎儿健康存活率较低.     

颈部透明层增厚与染色体异常的相关分析

目的:评估颈部透明层(NT)增厚胎儿的染色体异常风险,探讨染色体微阵列分析(CMA)在NT增厚时的应用情况。方法:回顾性分析374例于广州医科大学附属第三医院诊断为NT增厚胎儿的超声及CMA结果。结果:374例NT增厚病例中,109例(29.1%)染色体异常。在NT值为2.5～3.4 mm、3.4～4.4 mm、4.5～5.4 mm、≥5.5 mm 4组中每组病例数及染色体异常例数分别为114例,26例(22.8%);150例,33例(22.0%);55例,19例(34.5%);55例,31例(56.4%)。各NT值组染色体异常比较差异有统计学意义,NT增厚的程度与胎儿发生染色体异常正相关(ρ=0.208,P0.001)。NT增厚且合并其他超声异常者共64例,染色体异常率为60.9%(39/64),与单纯NT增厚胎儿染色体异常率(22.6%)比较,差异有统计学意义(χ~2=37.794,P0.001)。结论:早孕期胎儿NT增厚与染色体异常、其他超声异常密切相关;NT增厚的程度越大,胎儿发生染色体异常的风险越高。与单纯NT增厚胎儿相比,合并其他超声异常的胎儿染色体异常检出率更高。     

妊娠中期胎儿染色体病的产前诊断

目的 通过对妊娠中期高危孕妇羊水细胞染色体的核型分析，了解胎儿染色体核型异常发生情况。方法抽取1983年3月至2003年8月河南省人民医院342例符合产前诊断指征的妊娠中期孕妇羊水细胞进行培养，制备中期细胞染色体，用C、G、Q、R带等多种显带技术，进行染色体分析。结果在342例孕妇羊水中发现23例染色体异常，占6．7％，其中数目异常5例(21．8％)，嵌合体3例(13．0％)，结构异常15例(65．2％)。结论产前诊断胎儿染色体病最终仍需羊水染色体核型分析来确诊。     

低深度高通量全基因组拷贝数变异测序在487例颈项透明层增厚胎儿染色体分析中的应用

目的:应用低深度高通量全基因组拷贝数变异测序（copy number variation sequencing,CNV-seq）技术分析颈项透明层（nuchal translucency,NT）增厚胎儿的遗传学病因,初步探讨胎儿NT增厚与染色体异常的关系。方法:回顾性收集2018年1月至2020年12月在郑州大学第一附...     

妊娠早期胎儿颈部透明层厚度与胎儿预后的前瞻性队列研究

目的探讨妊娠早期胎儿颈部透明层(NT)厚度与胎儿预后的关系。方法收集2015年12月至2018年12月于南京大学医学院附属鼓楼医院行妊娠早期胎儿NT厚度测量的单胎孕妇,共4958例建立前瞻性研究队列,进行妊娠早期胎儿结构超声筛查、妊娠早期血清学筛查、妊娠中期超声筛查及对新生儿出生后28 d的体格检查。根据妊娠早期超声筛查的结果,分为胎儿NT增厚(≥3.0 mm)者167例与NT厚度正常者4791例;将胎儿NT增厚的孕妇,分为胎儿单纯NT增厚者86例与NT增厚合并结构异常者81例。分析不同NT厚度胎儿的预后,并重点对单纯NT增厚与NT增厚合并结构异常胎儿的妊娠结局进行分析。妊娠早期超声筛查发现胎儿结构异常或血清学筛查结果为高风险的孕妇,经绒毛穿刺取样术行染色体微阵列分析(CMA)检测以明确产前诊断。结果(1)胎儿NT厚度正常孕妇的妊娠结局:共4791例孕妇,包括胎儿NT厚度正常且无结构异常者4726例,其中妊娠中期及产后新诊断结构异常83例,4688例活产;胎儿NT厚度正常但结构异常的孕妇65例,其中61例孕妇终止妊娠,4例活产。(2)胎儿单纯NT增厚孕妇的妊娠结局:86例孕妇中,66例(76.7%,66/86)行CMA检测,3例胎儿诊断为21三体综合征;除7例孕妇选择终止妊娠外,余79例行妊娠中期超声检查、新生儿出生后28 d体格检查、新生儿电话随访至6~21个月均未发现发育异常。(3)胎儿NT增厚合并结构异常孕妇的妊娠结局:81例孕妇中,73例(90.1%,73/81)行CMA检测,其中32例的胎儿为染色体非整倍体异常。70例选择终止妊娠,2例妊娠中期自然流产,9例活产。(4)NT增厚是否合并结构异常胎儿的产前诊断结果及预后比较:单纯NT增厚的胎儿染色体非整倍体的发生率为3.5%(3/86),合并结构异常者为39.5%(32/81),两者比较,差异有统计学意义(χ2=32.7,P<0.01);胎儿单纯NT增厚孕妇的健康新生儿存活率为91.9%(79/86),合并结构异常者为9.9%(8/81),两者比较,差异有统计学意义(χ2=112.3,P<0.01)。结论妊娠早期,超声筛查胎儿NT及结构,能提高出生缺陷的产前筛查率。单纯NT增厚胎儿的染色体非整倍体的发生率较低,新生儿健康存活率较高。     

孕早期产前诊断中绒毛与胎儿染色体构成不一致的发生及对策

本文阐述了绒毛的发育过程及 CVS 时绒毛的三种细胞来源。综合绒毛与胎儿染色体构成不一致的典型病例,进行分类。统计了2,632例 CVS 中所发生的不一致在各类中所占的比重。从胚胎发生的角度,分类解释其不一致的发生过程。提出了不一致的处理对策。     

妊娠早期筛查Down综合征胎儿颈部半透明组织厚度的作用

Down综合征一直是产前遗传筛查的重点，其产前诊断必须依靠侵入性诊断。20世纪80年代中期后欧美等国逐渐将孕母血清学及超声标记用于Down综合征胎儿诊断前筛查，胎儿颈部半透明组织厚度(NT)是重要的超声标记，国外学者对其进行大量研究。复习妊娠早期筛查Down综合征胎儿NT的作用认为，在建立良好的质控并结合考虑妊娠周、妊娠年龄基础上，NT将成为妊娠早期有效、必选的Down综合征筛查标记。     

胎儿颈项透明层厚度与不良妊娠结局

目的 探讨胎儿颈项透明层(nuchal translucency,NT)厚度增加与妊娠结局的关系,以期用NT预测胎儿临床预后. 方法 研究对象为2009年2月13日至2010年5月16日在昆明医科大学第一附属医院门诊就诊并行超声检查的妊娠早期单胎孕妇1839例.参照英国胎儿医学基金会的指南测量胎儿头臀径及胎儿NT厚度,随访妊娠结局.将预测不良妊娠结局发生高风险的界值分为NT≥2.0、2.5、3.0、3.5、4.5 mm,应用不同的界值,通过绘制受试者工作特征曲线评估NT增厚对不良妊娠结局的预测作用,观察NT增厚对临床结局的影响.用卡方检验或Fisher精确概率法分析敏感性和假阳性率之间的差异. 结果 1839例孕妇发生不良妊娠结局49例,不良妊娠结局发生率为2.7％.NT界值分别为2.0、2.5、3.0、3.5及4.5 mm时,预测总不良妊娠结局的阳性似然比分别为1.6、3.4、12.4、51.0及92.0,不同NT范围不良妊娠结局的发生率依次为2.7％、1.0％、4.0％、17.0％及75.0％.正常妊娠结局的比例随着NT增厚而降低.NT预测总不良妊娠结局的受试者工作特征曲线下面积为0.647,95％CI为0.561～0.732. 结论 妊娠早期胎儿NT增厚与多种不良妊娠结局相关.不同界值下NT预测不良妊娠结局的发生率可为临床咨询提供客观依据,且NT预测不良妊娠结局的效力达中等水平.     

妊娠早期筛查Down综合征胎儿颈部半透明组织厚度的作用

Down综合征一直是产前遗传筛查的重点,其产前诊断必须依靠侵入性诊断.20世纪80年代中期后欧美等国逐渐将孕母血清学及超声标记用于Down综合征胎儿诊断前筛查,胎儿颈部半透明组织厚度(NT)是重要的超声标记,国外学者对其进行大量研究.复习妊娠早期筛查Down综合征胎儿NT的作用认为,在建立良好的质控并结合考虑妊娠周、妊娠年龄基础上,NT将成为妊娠早期有效、必选的Down综合征筛查标记.     

胎儿颈部水囊状淋巴管瘤病因、产前诊断及处理

胎儿颈部水囊状淋巴管瘤是发生在胎儿颈部最常见的异常，在高危妊娠妇女中，其发病率可达6．8％，胎儿存活率低，只有9．4％，危害严重。其病因可能是胎儿颈部淋巴管发育障碍引起的，常常合并有染色体的异常。超声检查是产前诊断的主要手段，并分为有分隔和无分隔两种类型。早期产前诊断、积极的宫内干预和及时的手术治疗能改善产后结局，提高新生儿存活率。     

Perinatal outcome in fetuses with extremely large nuchal translucency measurement

Background: Studies have suggested that an entirely normal outcome is likely when the nuchal translucency (NT) measurement is very large and the karyotype, morphology and echocardiography scans are normal. Recently this has been questioned as it is based on very small numbers.
Aim: Assess the outcome of pregnancies with an NT measurement of 6.5 mm or greater.
Methods: Audit of a large first trimester screening program.
Results: Over the ten years to 2006, 76 813 patients underwent first trimester screening, with 120 having an extremely large NT. Thirty-one cases had normal karyotypes, of which there were four sets of twins that demised. Six cases miscarried and ten were terminated, some with morphological abnormalities. Eight cases were still alive for the morphology scan, with the only abnormality being mild pyelectasis in one case. At birth, three cases were normal and another three cases had a good outcome. Two cases had coarctation of the aorta and a good outcome. One case had Noonan's syndrome, another had cerebral palsy and the case with pyelectasis had hydronephrosis, dilated ureters and some contractures.
Conclusions: When the karyotype and morphology scan are normal, the outcome is often good in spite of an extremely large NT. However, even a subtle ultrasound anomaly can indicate a genetic syndrome and echocardiography cannot exclude mild cardiac abnormalities.     

Technical aspects of nuchal translucency measurement

Nuchal translucency (NT) describes an echo-free area, below the skin, in the posterior nuchal and back region of the fetus and is typically observed in the first and early second trimester of pregnancy. A wide NT has been correlated with chromosomal and congenital abnormalities in the fetus. An accurate NT measurement is a critical component of the estimation of Down syndrome risk in the first trimester of pregnancy and the Nuchal Translucency Quality Review Program (NTQR) identified nine criteria that ensure an accurate measurement of NT during ultrasound examination. The purpose of this chapter is to present the technical aspects of obtaining an accurate NT measurement on ultrasound as outlined by the NTQR.     

Education and quality review for nuchal translucency ultrasound

First trimester nuchal translucency ultrasound has evolved from an ultrasound measurement used only in a research setting to a screening tool which is being offered to the general obstetric population. Studies of nuchal translucency suggest great variation in Down syndrome detection rates which may be secondary to significant differences in sonographic training and nuchal translucency image quality. Inaccurate screening has the potential to adversely impact patients. This paper will explore: (1) why quality review in nuchal translucency ultrasound is important, (2) methods of nuchal translucency quality assessment, (3) experience with quality review in the research setting, and (4) current strategies for quality assessment in patient care.     

The effect of image size on screen-positive rates for nuchal translucency screening

It has been shown previously that the absolute measurement of nuchal translucency (NT) thickness, one of the most effective screening tests for fetal Down syndrome, significantly decreases with increasing image size. We undertook a prospective study to assess whether this effect materially alters the NT-derived risk estimation for fetal Down syndrome. In 350 women, NT was measured at both 100 and 200% image sizes. The median NT measurement at 200% was 8% smaller than at 100%. The screen-positive rates at 100 and 200% image sizes were 5.1% (18/350) and 2.3% (8/350), respectively (P= 0.048). Altering the image magnification settings is likely to decrease the sensitivity of NT-derived Down syndrome risk estimation. Further study is required to test the effect of our finding on the sensitivity of NT screening and to assess whether adjustments in gain settings mitigate the effect.     

Fetal nuchal translucency in severe congenital heart defects: experiences in Northern Finland

Objective: To evaluate the performance of first-trimester measurement of fetal nuchal translucency (NT) in the detection of severe congenital heart defects (CHDs).

Methods: During the study period of 1 January 2008 – 31 December 2011, NT was measured in 31,144 women as a part of voluntary first-trimester screening program for Down’s syndrome in Northern Finland. NT was measured by personnel trained on the job by the experienced staff. No certification or annual audits are required in Finland. However, the recommendation is that the examiner should perform 200 scans on average per year. Severe CHD was classified as a defect requiring surgery in the first year of life or a defect that led to the termination of the pregnancy. All severe CHDs diagnosed during the study period in Northern Finland could not be included in this study since all women did not participate in the first-trimester screening and some cases were missing important data.

Results: Fourteen (17.7%) out of 79 severe CHDs were found with NT cutoff of 3.5?mm. Amongst the 79 severe CHD cases, there were 17 chromosomal abnormalities. With NT cutoffs of 2.0 and 1.5?mm the detection rates would have increased to 25.3% (n?=?20) and 46.8% (n?=?37). Using a randomly selected control group of 762 women with normal pregnancy outcomes, false positive rates (FPRs) were calculated. For NT cutoffs of 1.5, 2.0 and 3.5?mm, the FPRs were, 18.5, 3.3 and 0.4%, respectively.

Conclusions: A greater than 3.5?mm NT measurement in the first-trimester ultrasound is an indication to suspect a fetal heart defect but its sensitivity to detect severe CHD is poor. In our study, only 17.7% of severe CHDs would have been detected with an NT cutoff of 3.5?mm.     

Persistently elevated nuchal translucency and the fetal heart

Objective: To describe the outcome of fifteen cases with an elevated nuchal translucency (NT) which persisted into the second trimester as nuchal edema (NE) >6?mm whom underwent fetal echocardiography.

Materials and methods: Cases were identified following retrospective review of cardiac and genetic findings in fetuses with NE.

Results: Minor congenital heart disease was identified in 3/15 by the second trimester. Agenesis of the ductus venosus was evident in four. Pulmonary valve stenosis was diagnosed in one fetus at the 20-week scan and hypertrophic cardiomyopathy in one. However, hypertrophic cardiomyopathy or pulmonary valve stenosis was present after birth in all surviving cases by 3 months of age. On the basis of intention to treat, 11/12 survived to delivery and 9/12 survived to 28 days. There were 6 deaths before 14 months of age as a result of severe hypertrophic cardiomyopathy. Noonan syndrome was confirmed with genetic testing in 11/15 cases.

Conclusions: All fetuses with NT and NE had evidence of congenital heart disease at birth, and therefore, late gestation and postnatal review is recommended even when second trimester echocardiogram is considered normal. There is a high prevalence of Noonan syndrome and targeted genetic analysis should be considered. The outcome in these cases is poor.