1、 1CHINESE JOURNAL OF CT AND MRI,FEB.2023,Vol.21,No.02 Total No.160【第一作者】陈芳芳,女,主治医师,主要研究方向:影像诊断。E-mail:【通讯作者】刘影,女,主任医师,主要研究方向:神经影像诊断。E-mail:论 著Diffusion-weighted Imaging Evaluation of Middle and Late Pregnancy Fetal Brain with Cerebral AbnormalitiesCHEN Fang-fang,WU Ya-ling,LIU Meng-qiu,LI Shu-fang,L
2、I Shuang,LIU Ying*.Department of Radiology,the First Affiliated Hospital of USTC(Anhui Provincial Hospital),Hefei 230000,Anhui Province,China ABSTRACTObjective To evaluation the diagnostic efficiency of Diffusion-weighted imaging(DWI)in middle and late pregnancy fetal brain with cerebral abnormaliti
3、es by measuring apparent diffusion coefficient(ADC)values in different cerebral regions.Methods Half Fourier single-shot turbo spin-echo(HASTE)and DWI were performed in 43 singleton fetuses with normal or questionably fetal brain or placental lesions on sonography.ADC values in the frontal white mat
4、ter(WM),temporal WM,occipital WM,parietal WM,basal ganglia,thalamus,pons and cerebellum were measured respectively,and the differences between the two groups were compared.Meanwhile,the relationship between ADC values of different regions and gestational age was analyzed by Pearson correlation analy
5、sis.Results Among 43 singleton pregnant women,19 cases of fetal brain were in the normal control group,24 cases in the lesion group,including 16 cases of ventricular dilatation;6 cases of posterior fossa widening,1 case of arachnoid cyst,and one fetus had small head circumference.In the normal contr
6、ol group and the lesion group,the ADC values in the white matter area of the cerebral were higher than that in the deep nucleus,pons,and the cerebellum.In the two groups,the ADC values in the cerebellum and basal ganglia area were statistically significant compared with that in the thalamus and pons
7、.Moreover,the ADC values between the thalamus and brain stem were also statistically significant.The ADC values of the lesion group decreased,and there was statistical significance in ADC values of parietal WM between the two groups(P0.05).In the control group,occipital WM,parietal WM,and the cerebe
8、llum ADC values were negatively correlated with gestational age,while in the lesion group,thalamus,pons,and the cerebellum ADC values were negatively correlated with gestational age.Conclusion DWI could preliminarily evaluate the development of normal fetal brain and its associated lesions.The ADC v
9、alue of parietal WM in the lesion group decreased,which suggest that this region may be more sensitive to potential brain injury.Keywords:Fetal Brain,Diffusion Weighted Imaging,Apparent Diffusion Coefficient随着MRI技术的不断发展,其在产科领域的应用也越来越广泛,尤其是对胎儿脑部发育成熟的评价方面具有独特优势。弥散加权成像(diffusion weighted imaging,DWI)技术
10、通过测量水分子布朗运动获得表观弥散系数(apparent diffusion coefficient,ADC)反应活体内弥散信息。本文旨在通过DWI技术研究其在胎儿脑部及其合并病变的诊断价值。1 资料与方法1.1 一般资料 将我院2017年1月至2019年8月因产前超声怀疑胎盘或胎脑病变而行磁共振检查的43例孕妇作为研究对象,所有孕妇均为单胎,产前系统超声检查后24h内行MRI扫描。所有胎儿胎脑以外均未合并其他畸形及疾病。行MRI检查前孕妇均知晓该检查的敏感性、准确性及局限性,并签署知情同意书。1.2 检查方法 1.2.1 MRI检查 检查前对孕妇行屏气训练并告知检查注意事项,孕妇取仰卧位,足
11、先进。所有孕妇检查前未使用镇静剂。采用德国西门子公司生产的1.5T超导MRI仪对孕妇进行检查;8通道体部表面阵列线圈。先对孕妇的中下腹部行轴面、冠状、矢状面定位扫描,扫描范围包含整个子宫。再采用HASTE序列,根据以上三轴面对胎儿颅脑定位,行轴面、矢状面、冠状面扫描。HASTE扫描参数为:TR 1200ms,TE 84ms;FOV 400mm330mm,激励次数(NEX)为1,带宽488 Hz/pixel,矩阵256128或352192,反转角150,采集次数1 次,层厚3mm,间隔0mm。DWI的图像采用非屏气状态下扫描获取胎儿轴位颅脑弥散图像,扫描序列:TR 2000ms,TE90ms,视
12、野42cm42cm,矩阵 128128,激励次数(NEX)2.5,b值为0和1000s/mm2,扫描时间46s。将图像输入图像处理工作站,进行图像角度矫正。1.2.2 图像数据处理与分析 所有磁共振图像由2名高年资MRI诊断医师共同阅片,包括图像质量、颅脑结构及其有无合并脑内病变。通过MRI仪器自带后处理软件生成ADC图,并从ADC图中直接测量ADC值。将ROI左右对称放置于胎儿脑区,包括双侧额叶、枕叶、颞叶白质、顶叶、基底核区、丘脑、脑干及小脑,ROI放置点避免脑室、脑沟、皮质及血管等区域。每个ROI面积在1722mm2,每个位置测量2次,取其平均值作为各区域ADC值(图1)。1.3 统计学
13、分析 采用SPSS 19.0 统计软件进行统计分析,计量资料采用(-s)表示,磁共振弥散加权成像对孕中晚期胎脑及其病变的诊断评估 陈芳芳 吴亚玲 刘梦秋李淑芳 李 爽 刘 影*中国科学技术大学附属第一医院/安徽省立医院影像科(安徽 合肥 230000)【摘要】目的 通过测量不同脑区ADC值探讨MRI弥散加权成像对孕中晚期胎脑及其合并病变的诊断价值。方法 收集我院MRI检查的单胎孕妇43例,先行三平面常规T2HASTE扫描,再行弥散加权成像,分析胎儿磁共振表现并测量不同脑区的ADC值,比较两组间差异,采用Pearson相关分析不同区域ADC值与孕龄的关系。结果 43例孕妇均为单胎,正常对照组胎脑
14、19例,病变组24例,包括脑室扩张16例;颅后窝增宽6例,蛛网膜囊肿1例,1例胎儿头围发育较小。对照组及病变组内显示脑白质区ADC值均较深部核团、脑干及小脑增高,且有统计学意义;小脑及基底节区ADC值较丘脑及脑干有统计学意义;丘脑较脑干ADC值有统计学意义。两组间比较显示病变组顶叶ADC值较对照组下降,且P0.05。对照组枕顶叶及小脑与孕龄存在负相关,病变组丘脑、脑干及小脑与孕龄存在负相关。结论 MRI弥散加权成像可初步评估正常胎脑及合并病变的脑发育情况;病变组顶叶脑白质ADC值下降,提示该区域可能对脑部潜在损伤较敏感。【关键词】胎脑;磁共振弥散加权成像;表观扩散 系数【中图分类号】R714;
15、R445.2【文献标识码】A DOI:10.3969/j.issn.1672-5131.2023.02.0012中国CT和MRI杂志2023年02月 第21卷 第02期 总第160期病变组与对照组各脑区ADC值比较均采用独立样本t检验。胎脑左右两侧区域ADC值得比较采用配对样本t检验。P0.05为差异有统计学意义。两组中各脑区ADC值与孕周的关系采用Pearson相关分析。2 结 果2.1 胎儿头颅MRI检查相关临床因素 43例纳入研究的孕妇均为单胎,胎脑合并病变组共计24例,对照组正常胎脑19例,病变组孕妇年龄2137岁,平均年龄28岁,孕周2337周,平均孕周30周。对照组孕妇年龄2240
16、岁,平均年龄30岁,孕周2837周,平均孕周32周,前述各组间年龄、孕周比较差异均无统计学意义。2.2 常规MRI检查结果 24例胎脑合并病变组中包括脑室扩张16例,其中脑积水2例(1例侧脑室度宽为15mm、17mm,另外1例19mm、24mm),14例脑室轻中度扩张(10mm侧脑室宽度15mm);其中轻度侧脑室增宽约9例(10mm侧脑室宽度12mm),中度侧脑室增宽约5例(12mm侧脑室宽度15mm);颅后窝增宽6例,宽度约12mm22mm;蛛网膜囊肿1例;1例胎儿头围较小,与孕龄不符。除外1例一侧轻度侧脑室扩张合并局灶性小缺血灶;1例双侧侧脑室轻度增宽,合并可疑透明隔缺如,余下病例常规MRI提示脑实质信号未见明显异常改变(图2)。2.3 两组胎儿各区域ADC值比较及与孕龄关系 病变组两侧对称各区域ADC值分别为左右两侧额叶1.780.1410-3mm2/s、1.750.1510-3mm2/s;顶叶1.780.1310-3mm2/s、1.790.1510-3mm2/s;枕叶1.700.1610-3mm2/s、1.700.1610-3mm2/s;颞叶1.690.1110-3mm2/s、