摘要
目的探讨产前超声指标评分法对胎儿18三体综合征的诊断价值。方法采用前瞻性方法对2004年1月至2009年12月在中山大学附属第一医院行产前超声筛查孕妇中，发现胎儿结构或软指标异常者行胎儿染色体核型检查，根据胎儿染色体核型分析结果，分为18三体组和非18三体组。对两组胎儿任一异常超声指标进行单因素logistic回归分析，分别计算各超声指标的阳性似然比（＋衄）。＋LRi〉200的超声指标赋值3分，100≤＋职〈200的超声指标赋值2分，＋LR〈100的超声指标赋值1分。根据受试者工作特性（ROE）曲线，确定最佳诊断界值。结果（1）符合人选标准孕妇共26545例，产前超声检查可疑胎儿畸形或有超声软指标异常并接受胎儿染色体检查者共4044例，其中21三体93例，18三体59例，13三体19例，其他类型染色体异常134例，正常核型3739例。22501例胎儿产前超声检查无异常，3985例胎儿出生后随访其结局也无异常，共计26486例胎儿为非18三体组，59例18三体胎儿为18三体组。（2）18三体组59例胎儿均有2种及以上超声提示的结构异常，其中最常见为肢体异常（85％，50／59），其次是心脏畸形（83％，49／59）和中枢神经系统异常（75％，44／59）。肢体异常中以重叠指最常见，心脏畸形中室间隔缺损最多见，中枢神经系统畸形中最常见为“草莓头”型。（3）经logistic回归分析，所有超声异常指标中可进入回归方程的是脉络膜囊肿、“草莓头”型、后颅窝池增宽、前脑无裂畸形、耳低置、室间隔缺损、左心发育不良综合征等16项，按照此16项超声指标的＋加值分别得出不同分值。（4）18三体组和非18三体组产前超声评分1分值分别为2％（1／59）和2．549％（675／26486），4分值分别为9％（5／59）和0．215％（57／26486），9分值分别为10％（6／59）和0．004％（1／26486），10～16分值分别为32％（19／59）和0。（5）以不同总评分值为超声诊断18三体征的截断值，计算出各分值的敏感度和特异度，ROC曲线下面积为0．999。以总评分4分为最佳诊断值，诊断18三体征的敏感度为0．966，特异度为0．997。结论超声指标评分法对18三体综合征具有较好的诊断价值，以4分作为诊断18三体综合征截断值其诊断效价最高。
Objective To explore the value of sonogram index scoring system in the prenatal diagnosis of trisomy 18 syndrome. Methods Neonates who had prenatal sonographic screening in our tertiary center were followed up from January 2004 to December 2009. The fetuses who were suspected with abnormalities received karyotype analysis. All fetuses were divided into case group （trisomy 18 group） and the control group （ non-trisomy 18 group ）. The latter group was constituted of fetuses with trisomy 21, trisomy 13, other chromosomal abnormalitis and fetuses with normal karyotype. Logistic regression analysis was done to decide the individual sonographic features of trisomy 18. A score was assigned for ultrasound markers according to their likelihood ratios for trisomy 18 syndrome. A score of 3 was assigned for thesonographic teatures with likelihood ratio over 200, 2 tor those with likelihood ratio between 100 and 200, and 1 for those with likelihood ratio less than 100. The diagnostic efficacy of the ultrasound index scoring system was evaluated by diagnostic test. The optimal cutoff value was determined by receiver operating characteristic （ ROC ） curve. Results The study group included 59 fetuses with trisomy 18. And 26 486 fetuses did not have trisomy 18 syndrome, including 93 fetuses with trismoy 21, 19 fetuses with trisomy 13, 134 fetuses with other chromosomal abnormalities, 3739 fetuses with normal karyotype and 22 501 fetuses with normal appearance after birth. Two or more structural defects were observed in each trisomy 18 fetus. The highest incidence of sonogram abnormalities was extremities abnormalities （85%, 50/59）, followed by cardiac defects （ 83%, 49/59 ） and central nervous system （ CNS ） malformations （75% ,44/59）. Overlapping fingers, ventricular septal defect and strawberry-shaped skull were the most common abnormalities in extremities abnormalities, cardiac defects and CNS malformations, respectively. Logistic regression identified 16 markers, including choroid plexus cyst, strawberry-shaped skull, enlarged cisterna magna, holoprosencephaly, low-set ears, ventricular septal defect, hypoplastic left heart syndrome, etc. Different scores were assigned according to the likelihood ratios of these markers. In trisomy 18 group, fetuses with the sonographic score of 1,4,9,10 to 16 were 2% （1/59）, 9% （5/59）, 10% （6/59） and 32% （19/59） respectively, whereas in non-trisomy 18 group they were 2. 549% （675/26 486）, 0. 215% （57/26 486）, 0. 004% （1/26 486） and zero, respectively. When a score of 4 was used as the cutoff value for diagnosing fetal trisomy 18, the sensitivity and specificity were 0. 966 and 0. 997, respectively. The area under ROC curve was O. 999. Conclusions The ultrasound index scoring system may help to quantify the ultrasound features and has a good diagnostic value for fetal trisomy 18 syndrome. The cutoff value of 4 has the best diaznostic efficacy.
出处
《中华妇产科杂志》
CAS
CSCD
北大核心
2011年第11期845-849,共5页
Chinese Journal of Obstetrics and Gynecology
基金
国家自然科学基金面上项目（81071166）
广东省科委科技计划（20098080701061）
关键词
超声检查
产前
染色体
人
18对
三体性
Ultrasonography, prenatal
Chromosomes, human, pair 18
Trisomy
