MRI评估胎儿神经系统畸形

目的探讨MRI诊断胎儿中枢神经系统畸形的价值及其应用指征。方法回顾性分析450例中枢神经系统畸形胎儿的超声和MRI资料,与产后诊断或尸体检查结果进行对照。结果 450例患者共检出神经系统病变594处,包括单纯侧脑室增宽99处、脑积水21处、小脑延髓池增宽59处、Dandy-Walker畸形/小脑发育不良45处、胼胝体发育不良/缺如67处、透明隔增宽6处、脑白质软化15处、室管膜下囊肿/出血30处、颅内出血26处、颅内实质性病变14处、蛛网膜囊肿60处、孔洞脑13处、脑裂14处、积水型无脑畸形3处、脑水肿1处、平滑脑4处、脑组织发育不良3处、全前脑20处、小头畸形8处、头形异常3处、开放性神经管缺陷68处、脑血管畸形5处、透明隔缺如2处、颅底凹陷症1处、枕骨大孔窄1处、囊性松果体1处、脉络丛病变5处。超声正确诊断487处,准确率81.99%(487/594),MRI正确诊断551处,准确率92.76%(551/594)。结论对于胎儿神经系统各种病变,超声和MRI各有优劣,明确MRI应用指征有助于指导合理地选择产前MRI,从而明确诊断。

MRI in evaluating the fetal central nervous system abnormalities

Objective To explore the value and indications of MRI in diagnosing abnormalities of the fetal central nervous system (CNS). Methods MRI and ultrasound data of 450 fetuses with CNS maformations were retrospectively analyzed and compared with postpartum diagnosis or autopsy results. Results There were 594 CNS abnormalities detected, including 99 isolated ventriculomegaly, 21 hydrocephaly, 59 dilated posterior fossa, 45 Dandy-Walker malformation, 67 agenesis of corpus callosum, 6 dilated septum pellucidum, 15 brain leukomalacia, 30 ependymal cysts/haemorrhage, 26 intracranial hemorrhage, 14 intracranial solid lesion, 60 arachnoid cyst, 13 porencephaly, 14 schizencephaly, 3 hydranencephaly, 1 encephaledema, 4 smooth brain, 3 parenchymal dysplasia, 20 holoprosencephaly, 8 microcephalus, 3 cranial deformation, 68 open neural tube defects, 5 cerebrovascular malformation, 2 agenesis of septum pellucidum, 1 basilar invagination, 1 Foramen magnum narrow, 1 cystic pineal gland, 5 choroid plexus abnormity. The accuracy of ultrasonography and MRI were 81.99% (487/594) and 92.76% (551/594). Conclusion Ultrasound and MRI have advantages and disadvantages respectively in diagnosing fetal CNS. Definition of the MRI indications in detecting fetal CNS abnormalities is useful to guide reasonable use of fetal MRI to identify the diagnosis.