中孕期鼻骨测量结合血清学筛查检测胎儿染色体异常的价值

Value of nasal bone and serological screening for the detection of fetal chromosomal disorders in second trimester

目的 实施胎儿鼻骨测量联合血清学筛查（平行试验），评估平行试验对染色体异常检测率的影响。方法 于2009年1月至2010年12月在嘉兴市妇幼保健院超声检测6173例孕19～22周胎儿鼻骨长度。对其中血清学筛企高风险和（或）胎儿鼻骨异常的孕妇均做染色体核型分析。血清学筛查低风险且胎儿鼻骨正常者追踪随访其胎儿出生后婴儿状况。分析鼻骨长度与染色体异常的关系。结果 5607例胎儿鼻骨超声检测成功，成功率90．83％（5607／6173）；正常胎儿鼻骨长度随孕周增加而增长。血清学筛查染色体异常的敏感度为69．64％，血清学筛查分别联合胎儿鼻骨发育不良、胎儿鼻骨测量高风险对染色体异常检出的敏感度依次为79．76％、83．93％。结论 胎儿鼻骨发育异常与染色体异常有密切关系。中孕期超声测量鼻骨长度是筛佥胎儿染色体非整倍体异常和染色体片段异常的重要手段之一。平行试验可提高检出胎儿染色体非整倍体异常和染色体片段异常的敏感性。

Objective To assess the value of fetal chromosomal abnormality screening by a maternal serum test plus fetal nasal bone length in second trimester （parallel test）. Methods From January 2009 to December 2010, fetal nasal bone was measured at 19-22 weeks gestation in 6173 unselected cases. Karyotyping was performed in cases with a high risk for maternal serum test and/or abnormal fetal nasal bone length. All cases were followed-up postnatally. Results Nasal bone was assessed successfully in 5607 eases （90. 83% ）. Normally it is increases with gestational age. The detection rate of chromosomal abnormality was 69. 64% by maternal serum test, 79. 76% by maternal serum test plus hypoplastic nasal bone and 83.93% by maternal serum test plus shortened nasal bone. Conclusion Fetal nasal bone hypoplasia is closely correlated with chromosomal abnormality. And sonographic evaluation of nasal bone may be a useful tool for screening chromosomal abnormality. The combination of maternal serum test and fetal nasal bone length will boost the detection rate of chromosomal abnormality.