MRI诊断为脊髓栓系胎儿的妊娠结局:38例分析

Pregnancy outcome of fetal tethered cord diagnosed by MRI:analysis of 38 cases

目的评价MRI诊断为脊髓栓系胎儿的妊娠结局。方法回顾性分析2015年1月至2019年8月复旦大学附属妇产科医院经MRI诊断为脊髓栓系的38例胎儿(36例为单胎,2例为双绒毛膜双羊膜囊双胎之一)的资料。根据脊髓圆锥与膀胱的位置关系形态,将这些病例分为高于膀胱组和低于膀胱组。分析不同脊髓圆锥位置病例的妊娠结局。采用Fisher精确概率法及Student t检验等方法分析数据。结果(1)38例的MRI检查孕周为(25.5±4.7)周,其中14例(36.8%)为单纯脊髓栓系,24例(63.2%)合并其他结构异常。合并结构异常以脑脊膜膨出为多(15例)。24例(63.2%)超声与MRI结果基本一致,另14例(36.8%)超声只提示椎体形态学异常,经MRI进一步检查发现脊髓栓系。(2)38例中,29例(76.3%)选择引产,1例(2.6%)于孕23周行减胎术(另一正常胎儿早产分娩),1例(2.6%)失访。7例(18.4%)单胎继续妊娠并最终分娩。生后随访8.1个(4.0~54.9个)月,2例无合并症患儿生长发育未见异常,3例生后行手术治疗,2例于新生儿期死亡。(3)所有病例的脊髓圆锥宽度平均值是(2.5±0.8)cm。高于膀胱组(34例)和低于膀胱组(4例)的脊髓宽度[(2.5±0.8)与(2.7±1.1)cm]差异无统计学意义。高于膀胱组6例(17.6%)继续妊娠至分娩,其中1例因重度脑积水死亡;低于膀胱组1例(1/4)继续妊娠至分娩,新生儿期因窒息死亡。结论单纯脊髓栓系胎儿预后一般较好。脊髓圆锥位置高低与妊娠结局的关系有待进一步研究。

Objective To evaluate the pregnancy outcomes of fetal tethered cord(TC)prenatally diagnosed by MRI.Methods Clinical data of 38 fetuses diagnosed as having TC by MRI,including 36 singletons and two fetuses who were both one of dichorionic diamniotic twins,were retrospectively collected and analyzed in the Obstetrics and Gynecology Hospital of Fudan University from January 2015 to August 2019.According to whether conus medullaris was located above the bladder or reached the lower edge of the bladder,all cases were divided into high or low groups.Pregnancy outcomes were compared between the two groups using Fisher's exact test and Student's t-test.Results(1)The gestational age at MRI was(25.5±4.7)weeks.Among the 38 cases,14(36.8%)were isolated TC,24(63.2%)were complicated by other anomalies.The meningocele was responsible for the most(39.5%,n=15).The results of the ultrasound were consistent with those of MRI in 24 cases(63.2%).While in the other 14 cases(36.8%),the ultrasound only showed vertebral body's abnormal morphology,after which further MRI examination revealed a tethered cord.(2)Twenty-nine women(76.3%)chose to terminate the pregnancy.One patient(2.6%)underwent fetal reduction at 23 gestational weeks(one normal twin was delivered prematurely),and one(2.6%)was lost to follow-up.Seven(18.4%)cases continued the pregnancies to delivery.The postnatal follow-up period was 8.1 months(4.0 to 54.9 months).Two infants without comorbidities showed normal growth and development.Another three cases underwent surgeries after birth,and two cases died in the neonatal period.(3)The average width of the medullary cone was(2.5±0.8)cm.There was no significant difference in the spinal cord width between the high[(2.5±0.8)cm,n=34]and low group[(2.7±1.1)cm,n=4].Six pregnancies(17.6%)in the high group was continued to delivery,and one of the neonates died of severe hydrocephalus.One patient in the low group(1/4)was delivered,while the baby died of neonatal asphyxia.Conclusions Fetuses with isolated TC are prone to have a good prognosis.Further study should focus on the relation between the high or low position of the conus medullaris and pregnancy outcomes.