3.0T MRI诊断胎儿骶尾部畸胎瘤

目的:探讨3.0T MRI对胎儿骶尾部畸胎瘤诊断价值。方法:分析17例胎儿骶尾部畸胎瘤产前超声、MRI及术后病理、随访资料。产前超声检查后48h内行MRI检查。T2WI采用半傅立叶单次激发快速自旋回波(HASTE)序列及真稳态进动快速成像(true-FISP)序列,T1WI采用二维快速小角度激发(FLASH)序列,行胎儿骶尾部冠状面、矢状面及横断面扫描。将产前MRI、超声表现与出生后影像、手术或引产胎儿尸检结果对照分析。结果:17例胎儿骶尾部畸胎瘤产前MRI表现:囊性肿块4例、囊实性肿块11例,实性肿块2例;畸胎瘤Ⅰ型5例、Ⅱ型7例、Ⅳ型5例;12例出现邻近组织受压性改变,7例显示可疑椎体破坏。17例中4例行产后手术,产后复查CT与产前MRI结果基本一致,术后均证实为成熟性畸胎瘤。13例引产后经病理证实为非成熟性畸胎瘤4例,成熟性畸胎瘤9例。结论:产前MRI检查可直观显示胎儿骶尾部畸胎瘤解剖结构,为产前临床处理方案提供精准影像依据。

The diagnostic value of 3.0T MRI in fetal sacrococcygeal teratoma

Objective:To explore the diagnostic value of fetal sacrococcygeal teratoma by using of 3.0T MRI.Methods:There were 17 cases of fetal sacrococcygeal teratoma.Prenatal US findings,MR imaging,postoperative pathology and follow-up data were analyzed retrospectively.All cases were studied with a 3.0T MRI unit within 48 hours after ultrasound exam.HASTE(half-Flourier acquisition single-shot turbo spin-echo)T2WI,true-FISP(true fast imaging with steady state precession)T2WI,and FLASH(fast low angle shot)T1WI of fetal sacrococcygeal region in axial,coronal and sagittal planes were performed.Prenatal MR imaging and US findings were compared with postnatal pathologic results or autopsy.Results:In all l7 cases,there were three types of fetal sacrococcygeal teratoma including cystic mass(n=4),solid-cystic mass(n=11)and solid mass(n=2).There were 5 cases of typeⅠ,7 cases of typeⅡand 5 cases of typeⅣ.Adjacent structure compression(n=12)and suspicious vertebral body destruction(n=7)were shown on prenatal MRI.4 cases were diagnosed as mature teratomas by postpartum pathology,and the findings of postnatal CT were matched with prenatal MRI.In other 13 cases,there were 4 cases of immature teratoma and 9 cases of mature teratoma proven by autopsy after induced labour.Conclusions:Prenatal MRI can clearly display fetal sacrococcygeal teratoma and provide accurate imaging imformation for prenatal intervention.