激光凝固胎盘吻合血管术治疗单绒毛膜双羊膜囊双胎并发选择性胎儿生长受限的临床效果分析

Clinical effects of treatment of sIUGR in MCDA pregnancies by fetoscopic laser photocoagulation

目的 探讨胎儿镜下激光凝固胎盘吻合血管术治疗单绒毛膜双羊膜囊双胎（MCDA）并发选择性胎儿生长受限（sIUGR）的临床效果.方法 收集2004年11月至2011年2月香港中文大学威尔斯亲王医院妇产科学系胎儿医学组收治的5例MCDA并发sIUGR孕妇的临床资料并进行回顾性分析.结果 5例MCDA并发的sIUGR均为Ⅱ型,5例生长受限胎儿（小胎）羊水过少,脐带在胎盘边缘附着,其中3例存在静脉导管血流频谱a波倒置.5例孕妇行胎儿镜下激光凝固胎盘吻合血管术时的中位孕周是19周（16周＋1～22周＋1）;5例孕妇的双胎胎儿染色体核型分析结果均正常;无术中并发症发生;术后5例小胎均于两周内宫内死亡;术后5例生长正常儿（大胎）生长发育各项指标、羊水量、大脑中动脉收缩期峰值流速均在正常范围;5例大胎均为早产,中位分娩孕周为32周（30周＋3～34周）,大胎中位出生体质量为1 540 g（1 100 ～2080 g）;术后胎儿整体存活率为5/10,至少1胎存活率为5/5;5例孕妇分娩后检查胎盘经激光凝固的胎盘血管吻合支呈“苍白”颜色.5例孕妇分娩后胎盘病理检查确认为单绒毛膜性.结论 胎儿镜下激光凝固胎盘吻合血管术治疗MCDA并发sIUGR安全有效,即使小胎发生宫内死亡,大胎生长也不受影响,从而提高了大胎的围产期生存率.

Objective To study the outcome of fetoscopic laser photocoagulation （laser） in the management of monochorionic diamniotic twin （MCDA） pregnancies complicated with selective intra-uterine growth restriction （sIUGR）.Methods Retrospective analysis of 5 MCDA twin pregnancies with sIUGR treated by laser.Results All 5 cases were sIUGR type Ⅱ.In all 5 cases,the growth restriction was associated with oligohydamnios,and the umbilical cord had marginal insertion to the placenta.Abnormal Doppler flow pattern of the ductus venosus was present in 3 cases.Indication for laser therapy was beause of high risk of deterioration and fetal demise of the growth restricted fetus.In all cases,fetal reduction as an alternative was discussed and was refused.The median gestation at laser was 19 weeks.The procedure was successful in all cases,with complete seperation of the vascular anastomoses.There was no case of immediate postoperative complications.Fetal karyotype was normal in all cases.Fetal death of the small twin occurs in all cases within two weeks after surgery.Follow up studies of the surviving twin in all cases showed normal fetal growth,amniotic fluid volume,and middle cerebral artery peak systolic velocity.All cases resulted in preterm labor,with a median gestational age of 32 weeks （30＋3 weeks to 34 weeks）,and a median birth weight of 1 540 g （1 100-2 080 g） ; the postoperative fetal survival rate was 5/10,with at least one child survival rate of 5/5.There was no neonatal complication in the survival twins.Postnatal pathological examination of the placenta confirmed MCDA twin in all cases.Conclusions Laser treatment of MCDA twin complicated with sIUGR is effective.It protects the normal fetus even when the growth restricted twin died.However,the intention to give a small chance of survival to the growth restricted fetus by avoiding fetal redution procedure was not successful.All of the sIUGR fetuses died due to placental insufficicent.This fact is important during the pre-treatment counselling to avoid unrealistic expectation.