颈项透明层增厚胎儿的产前诊断和预后研究

目的 探讨颈项透明层增厚与胎儿染色体异常、严重结构畸形和其他严重异常的关系,了解其在评估胎儿预后中的价值。方法 回顾性分析2008年1月~2014年1月于宜宾市第二人民医院78例妊娠早期11~13+6周NT≥2.5 mm且行产前诊断的单胎的临床资料,按NT厚度将其依次分为3组。第1组(NT 2.5~3.5 mm,34例)、第2组(NT 3.6~4.5 mm,28例)及第3组(NT≥4.6 mm,16例)。统计胎儿染色体核型检测结果,随访胎儿超声筛查结构异常情况及妊娠结局。结果 178例NT增厚胎儿中染色体核型异常22例(28.21%)、结构异常23例(29.49%),其中严重心脏畸形14例(17.95%)。随访率96.15%(75/78)。妊娠结局:引产39例,活产36例,无宫内感染、胎膜早破等妊娠结局,活产36例均无出生缺陷。2三组NT增厚胎儿中染色体异常发生率分别为17.65%、28.57%、50.00%,严重心脏畸形发生率分别为0.00%、21.42%和50.00%,结构异常发生率分别为20.59%、28.57%和50.00%。三组胎儿染色体异常、结构异常及心脏畸形的发生率差异均有统计学意义(P<0.05),且发生率均随NT增厚而升高。3主要染色体异常包括21三体综合征(10.26%)、心脏畸形异常(7.69%)和18三体综合征(3.85%)。结论 NT增厚与胎儿染色体非整倍体和先天性心脏病等不良妊娠结局有关。     

Prenatal diagnosis of Down syndrome: A 13-year retrospective study

Objective

The aim of this study is to summarize the experience on prenatal diagnosis of Down syndrome.

胎儿颈项透明层厚度在早孕期筛查胎儿畸形的研究进展

孕11-13＋6周胎儿颈项透明层（NT）厚度已经成为早孕期筛查唐氏综合征的重要指标。NT增厚除了与染色体病密切相关外,还与先天性心脏病、胎儿畸形、贫血、感染等因素相关。但是,仍有相当一部分NT增厚的胎儿,出生后是完全正常的。因此,如何对胎儿NT增厚的孕妇进行产前诊断？如何对NT增厚但染色体核型正常的产前病例进行产科处理？NT一旦增厚是否不需要进行唐氏筛查而直接进行产前诊断？这些问题都是目前临床亟待解决的主要问题[1]。本文对国内外相关的文献进行综述,旨在从NT增厚的原因、病理基础、产科处理及妊娠结局等多个角度对NT增厚的产前咨询策略作一探讨,以期为NT测量的临床应用提供科学的理论依据。     

早孕期超声筛查胎儿巨膀胱的临床价值分析

目的探讨规范化早孕期超声筛查胎儿巨膀胱的临床特征，为其临床管理提供依据。 方法回顾性分析2018年1月至2022年1月间于郑州大学第三附属医院产前超声诊断中心行规范化早孕期产前筛查的妊娠11~13⁺⁶周孕妇43 862例的产前资料，对检出的巨膀胱胎儿，记录膀胱大小、彩色多普勒显示脐动脉，追踪妊娠过程及临床结局，通过产后复查、病理检查和介入性产前诊断等方法进一步明确病因。 结果超声筛查检出胎儿发育异常952例，其中巨膀胱胎儿64例。巨膀胱胎儿合并颈后透明层增厚者10例，合并染色体异常者10例，合并脐带囊肿者11例，合并单脐动脉者21例，合并肾回声增强者9例，早孕期显示“钥匙孔”征（+）者11例，早孕期合并心脏异常者6例，合并颜面异常者2例，合并腹壁肌层异常者7例，合并肢体骨骼异常者8例；64例巨膀胱胎儿中43例进行选择性终止妊娠，15例在随访过程中停止发育，2例出生未见异常，4例男性胎儿出生后行下尿路梗阻部手术，且尸检证实有5例为梅干腹综合征。 结论早孕期超声筛查可有效地检出和诊断胎儿巨膀胱，并可对其可能存在的病因及临床结局提供适宜的建议，有助于尽早产科处理与临床管理。     

孕11—13^＋6周胎儿颈项透明层厚度的超声测量

目的分析孕11～13^＋6周正常胎儿颈项透明层（NT）厚度及其与头臀径的关系。方法选择孕11～13^＋6周头臀径为45～84mm的正常胎儿3224例，超声测量胎儿NT厚度和头臀径，并对头臀径与颈NT厚度进行相关性研究。结果胎儿NT厚度随着头臀径的增加而增厚；中位数预测值从头臀径为45mm时的0．9mm至头臀径为84mm时的1．7mm。结论孕11-13^＋6周正常胎儿NT厚度的参考值范围为早孕期胎儿染色体异常和其他先天性异常的筛查提供了帮助。     

Does increased nuchal translucency indicate a fetal abnormality? A retrospective study to clarify the clinical significance of nuchal translucency in Japan

The results of a chromosomal test by genetic amniocentesis in 58 cases with an increased nuchal translucency (NT; > or =3 mm thickness) revealed 47 cases showing a normal karyotype (81%) and 11 cases (19%) showing an abnormal karyotype. However, the cases of a normal karyotype with increased NT also included those with fetal abnormalities. Among the 49 cases in which NT was observed during the first trimester and then subsequently disappeared, chromosomal abnormalities were observed in five, and fetal abnormalities other than chromosomal abnormalities were observed in two. Meanwhile, all nine cases in which an increased NT remained or in which NT continued to increase in size during the second trimester were diagnosed as having cystic hygroma, and chromosomal abnormalities were found in six cases (67%). It should be noted that the shape of increased NT includes NT with a notch (notched NT) and NT without a notch (smooth NT). Among the 20 cases of notched NT, chromosomal abnormalities were observed in eight (40%), and cystic hygroma was observed in nine (45%). On the other hand, among the 38 cases of smooth NT, chromosomal abnormalities were observed in three (7.9%), but no cystic hygroma was observed. Our results confirm that increased NT does not always indicate a fetal abnormality. Whether NT thickness should be measured as a screening tool for fetal abnormalities remains controversial. However, increased NT may be detected by chance, because a maternal-fetal medical examination using ultrasonography is usually performed in Japan. It is therefore considered to be extremely important to establish a system in which cases are referred to obstetricians who are licensed clinical genetic specialists to obtain appropriate genetic counseling whenever increased NT is clinically observed.     

Comparison of Nicolaides’ risk evaluation for down’s syndrome with a novel software: an analysis of 1,463 cases

Objective The individual risk assessment of fetal Down’s syndrome based on measurement of nuchal translucency (NT) according to Nicolaides, optionally complemented by the determination of PAPP-A and free beta HCG has progressively supplanted other search strategies for fetal aneuploidies. It could be shown that this diagnostic strategy equally detects other numeric aneuploidies at a comparable rate. A positive test result is also predictive for the presence of a fetal malformation. In this field, several computer programs are available for clinical use. The objective of our study was to re-evaluate the first consecutive 1463 NT-risk calculations determined by Nicolaides’ method and to compare the risk calculation to the JOY software (NT-risk calculation module, JOY Patient Database) introduced in 2002. Material and methods At the Department of Obstetrics and Gynecology, Hannover Medical School, 1463 consecutive complete data sets comprising first trimester screening performed between May 2, 2000 and June 26, 2003 and corresponding fetal outcome were analysed using risk assessment based on the Nicolaides method (PIA Fetal Database NT-Module) and compared with the risk evaluation as determined by the JOY software (JOY Patient Database NT module). A risk exceeding 1:300 was considered to indicate the need for further invasive testing. In a first step, only cytogenetically detectable chromosomal aberrations were analysed. Then, a second evaluation including fetal malformations was performed. Results Among the 1463 cases, 1445 (98.77%) fetuses revealed to be cytogenetically healthy. Both softwares showed identical detection rates at the genetic and somatic level:13 cases of Down-Syndrome (0.89%), 2 cases of trisomy 18 (0.14%), one case of triploidy, one Turner-Syndrome, one Klinefelter-Syndrome (0.07% each) were detected. A positive test result was found in 15 cases ending in a spontaneous abortion, intrauterine death or peripartum death (1.03%) and in 22 cases of fetal malformation (1.50%). At the level of genetic detection the test positive rate dropped from 92 (PIA) to 71 (JOY) (-22.8%). At the level of combined adverse outcome the test positive rate was reduced from 100 (PIA) to 76 (JOY) (-22.0%), thus yielding in a marked improvement of the characteristic test performance parameters. Conclusion The novel, recently developed JOY software package allowed reliable evaluation of the risk for aneuploidy with increased specificity whereas sensitivity was unchanged. Our data suggest an improvement of the screening for aneuploidy when using this novel software: With an identical detection rate, the number of unnecessary invasive measures may be reduced.     

孕早期胎儿颈项透明层在产前超声筛查胎儿畸形中价值的Meta分析

ObjectiveTo evaluate the value of nuchal translucency (NT) as a screening test for fetal abnormalities in the first trimester ultrasound examination.MethodsA search in Cochrane Library, PubMed, OVID, Springer, China National Knowledge Infrastructure (CNKI) and Chinese Bio-edicine Database（CBM）was performed to identify relevant English and Chinese articles between Jan 1990 and August 2008. Criteria for inclusion were established based on validity criteria for diagnostic research. Subsequently, the characteristics of the included articles were extracted. Statistical analysis was performed with Meta-iSc 1.4. Heterogeneity of the included articles was tested to select proper effect model to calculate pooled weighted sensitivity and specificity. Summary receiver operating characteristic curve(SROC) was made and the area under the curve (AUC) was calculated. Finally, sensitivity analysis was performed.ResultsTwelve articles were included, with a total of 112 099 fetuses. Nine articles meeting inclusion criteria were analyzed for the value of screening for cardiac abnormalities by nuchal translucency thickness above the 95th percentile for gestational age. The pooled sensitivity and specificity was 29.8%, 96.9%，respectively, AUC=0.804 7. Seven articles meeting inclusion criteria were analyzed for the value of screening for cardiac abnormalities by nuchal translucency thickness above the 99th percentile for gestational age. The pooled sensitivity and specificity was 18.9%, 99.3%，respectively, AUC=0.971 2. Five articles meeting inclusion criteria were analyzed for the value of screening for fetal abnormalities by nuchal translucency thickness above the 95th percentile for gestational age. The pooled sensitivity and specificity was 25.0%, 98.3% respectively, AUC=0.183 0. The sensitivity of screening for cardiac abnormalities by nuchal translucency thickness above the 95th percentile for gestational age was significantly higher than the nuchal translucency thickness above the 99th percentile for gestational age（χ2=6.58， P<0.05）,no difference was found in the specificity. The random?瞖ffect model was used in the analysis of screening for cardiac abnormalities by nuchal translucency thickness above the 95th or 99th percentile for gestational age because of the heterogeneity. The fixed-ffect model was used in the analysis of screening for fetal abnormalities by nuchal translucency thickness above the 95th percentile for gestational age because of the homogenicity. ConclusionsThe results suggest that screening for fetal abnormalities by NT thickness above the 95th percentile for gestational age has a low accuracy and is unsuitable for prenatal screen. At present it is incompletely clear on the sensitivity and specificity of screening for different kinds of fetal abnormalities by NT thickness. Screening for cardiac abnormalities by first trimester NT thickness has a high accuracy and specificity and can be reliably used in prenatal screen. We need the further systemic reviews to evaluate the value of NT as a screening test for different kinds of fetal abnormalities. Further multi?瞔entre and prospective studies are badly needed to be performed to optimize the standard of nuchal translucency thickness, evaluate the value of NT as a screening test for fetal abnormalities (especially cardiac abnormalities) in the first trimester ultrasound examination by a cost-effectiveness analysis, and develop an operation guideline on first trimester nuchal translucency thickness measurement for the prenatal screening of cardiac abnormalities in China.     

Early resolution of increased nuchal translucency in a fetus with trisomy 18

The normal timing for first-trimester nuchal translucency screening of aneuploidies is 10 to 14 weeks' gestation. We describe a fetus with trisomy 18 that presented at 11 weeks with increased nuchal thickness. Reevaluation at 12 and 13 weeks showed early return to normal of the increased nuchal measurement.