产前超声诊断双胎反向动脉灌注综合征

Prenatal diagnosis of twin reversed arterial perfusion sequence through ultrasonography

目的探讨多普勒超声在产前诊断双胎反向动脉灌注综合征（TRAP）中的临床价值，提高对此类罕见畸形的认识。方法我院1995年1月至2008年9月产前超声诊断及疑似诊断19例TRAP，比较超声与生后随访或引产后病理结果。结果19例TRAP中，无心畸胎（受血儿）均有严重结构畸形，产前超声对胎儿皮肤水肿、脊柱、腹腔结构及下肢显示准确性高；但对头颅发育不良及特别短小的上肢显示困难，颜面部畸形基本上显示不清。泵血儿（供血胎）中死胎及死产16例，存活3例；心功能不全9例。胎儿附属结构特征：（1）存活的无心畸胎均为脐动脉供血，血流方向朝向胎儿体内，与正常胎儿脐动脉血流方向相反；（2）两胎儿脐带胎盘附着处可见大的血管相交通；（3）无心畸胎多为单脐动脉；（4）羊水过多为预后不良征象；（5）单羊膜囊双胎常发生脐带缠绕及打结。结论多普勒超声可为评价TRAP血流动力学特征、评估泵血儿心功能、附属物异常及预后提供重要信息，为产前诊断TRAP的首选和重要的诊断方法。

Objective To explore the clinical value of color Doppler ultrasonography in diagnosing twin reversed arterial perfusion sequence （TRAP）and improve early diagnosis of this rare fetal malformation. Methods From January 1995 to September 2008, 19 TRAP were diagnosed or suspected by prenatal ultrasonography in our hospital. The final diagnosis was confirmed by ultrasound after birth or autopsy. Relative information of the 19 cases were collected and analyzed retrospectively. Results Among the 19 TRAP fetuses, all the recipients had severe and lethal developmental abnormalities. Prenatal ultrasonography was highly accurate in demonstrating skin edema, spine, abdominal organ and lower limbs, but found difficulty in cranial dysplasia and microsoma upper limbs and was not able to demonstrate facial malformations. Among the 19 donors, 3 survived and 16 died. Cardiac insufficiency was detected in 9 cases. The structural features of fetal appendages incluced： （1） All alive recipients were supplied by umbilical artery draining towards the fetus, which was different from normal fetus. （2） Abnormal placental vascular anastomoses was found between the two fetuses. （3） The cord of the recipient, the acardiac fetus, had single umbilical artery. （4） Polyhydramnios predicted poor prognosis. （5） Entanglement and knot of umbilical cord usually happened in monoamniotic twins. Conclusions Color Doppler ultrasonography could provide important information in evaluating the hemodynamics characteristics of TRAP, cardiac function of the donor fetus, abnormalities of fetal appendages and in predicting prognosis and is the first choice for prenatal diagnosis of TRAP.