胎儿小脑蚓部发育的MRI研究  

MRI assessment of fetal cerebellar vermis development

作　　者：开治国[1] 王光彬[2] 张忠和[3] 

机构地区：[1]山东省济南市第四人民医院,山东济南250031 [2]山东省医学影像学研究所,山东济南250021 [3]山东大学医学院,山东济南250012

出　　处：《中国中西医结合影像学杂志》2012年第2期109-111,114,共4页Chinese Imaging Journal of Integrated Traditional and Western Medicine

摘　　要：目的:描述正常胎儿标本小脑蚓部在不同孕周的正常发育生长曲线,并探讨胎儿丹迪-沃克综合征(DWS)的MRI表现。方法:对63例胎龄15～40周的胎儿标本行3.0T MRI扫描,从中选出52例符合要求的进行测量,扫描序列为T1WI、T2WI;扫描方位:矢状位扫描为主,辅以冠状位及横轴位;观察及测量内容:测量小脑蚓部的前后径(正中矢状面第四脑室顶点至水平裂处蚓部后缘最大距离)、上蚓高度及下蚓高度(上蚓的最高点及下蚓的最低点分别到前后径线的垂直距离)。对上述测量结果与孕龄间作回归分析。然后对6例经MRI诊断为DWS的病例进行回顾性分析。结果:小脑蚓部前后径、上蚓高度及下蚓高度分别与孕龄呈线性正相关,而上蚓高度总是略大于下蚓高度(P<0.05),多数标本正中矢状面T1WI、T2WI可清晰显示原裂及下后裂。DWS主要表现为小脑蚓部缺如或发育不良,测量数据小于正常胎儿,第四脑室与后颅窝囊肿相通或小脑延髓池增宽。结论:MRI可明确显示正常胎儿小脑蚓部在17孕周以后的正常发育表现及变化规律,而DWS的MRI表现具有特征性,MRI是诊断DWS最理想的影像学方法。Objective： to measure the main dimensions of fetal cerebellar vermis and assess its development.To explore the MRI features of Dandy-Walker syndrome（DWS）.Methods： 52 of the 63 fetal specimens（gestational age 15-40 weeks）scanned on a 3.0T MR system met the inclusion criteria.The anterior posterior diameter（APD）of cerebellar vermis,the height of anterior vermis and posterior vermis were measured and analysed.The MRI findings of DWS（n=6）confirmed by MRI scan were analyzed retrospectively.Results： APD and the height of anterior vermis and posterior vermis increased linearly with gestational age,the height of anterior vermis was greater than posterior vermis（P〈0.05）,primary and infero-posterior fissure could be visualized on midsagittal T1 and T2-weighted images.The main MRI findings of DWS were observed as follows：absence of the cerebellar vermis or partial agenesis of the separative cerebellar hemispheres,cystic dialation of the fourth ventricle communicating with enlargement of posterior fossa cyst.Conclusion： The development of fetal cerebellar vermis could be assessed by MRI after a gestational age of 17 weeks.There are characteristic MRI findings in the DWS and MRI scan is a valuable method for an early diagnosis of DWS.

关 键 词：胎儿 小脑 磁共振成像 丹迪-沃克综合征 

分 类 号：R445.2[医药卫生—影像医学与核医学] R714.5[医药卫生—诊断学]