胎儿大脑皮层观察的新方法：三维颅脑表面反转成像法

目的研究三维颅脑表面反转成像法在产前评价正常胎儿颅脑沟回的临床应用价值。 方法选取2019年6月至2020年7月在深圳市妇幼保健院行产前超声检查诊断无结构异常的133例19~36周正常单胎胎儿作为研究对象。观察不同孕周外侧裂、顶枕沟、距状沟在超声二维、三维表面成像中的显示、变化情况。检查结果按胎龄分为6组,按缺失或存在进行统计,形态变化汇总成图片。采用Pearson χ²检验比较二维超声和三维新方法对外侧裂、顶枕沟、距状沟显示率的差异。随机抽取30例胎儿进行研究者内和研究者间的重复性检验。 结果随着妊娠周数的增加,胎儿颅脑外侧裂、顶枕沟、距状沟的二维和三维超声检查的显示率都越来越高。二维、三维超声对22周外侧裂,23周、24~36周外侧裂、顶枕沟和距状沟显示率均达100%。二维观察与三维反转成像法的超声显示率差异无统计学意义（P均＞0.05）。三维反转成像显示沟回变化比二维超声更直观,更加接近实际解剖形态的变化。研究者内和研究间重复性检验显示一致性均可接受（Kappa系数均＞0.7）。 结论三维反转成像法可以直观形象地观察顶枕沟、距状沟、外侧裂的形态及空间变化情况,对于产前评估大脑皮层发育是一种补充手段,为未来大脑皮层发育的教学与研究提供了一种新的思路。     

超声评估复杂型先天性心脏病胎儿脑发育

目的:采用二维和频谱多普勒超声测量先天性心脏病(congenital heart disease,CHD)胎儿脑沟的深度及脑血流参数,以评估CHD胎儿脑发育情况。方法:选取2016年6月至201 8年6月于保定市第一中心医院行产前超声检查,发现复杂型CHD胎儿34例。同时选取同孕周超声检查正常胎儿34例为对照组。分别测量正常组和CHD组胎儿大脑中动脉搏动指数(middle cerebral artery pulsatility index,MCAPI)、脐动脉搏动指数(umbilical artery pulsatility index,UAPI)、脑-胎盘比(cerebroplacental ratio,CPR)、顶枕沟深度、外侧裂深度、距状沟深度,比较两组间各参数的差异。采用新生儿行为神经测定(neonatal behavioral neurological assessment,NBNA)量表评估新生儿脑损伤情况,比较两组间NBNA评分差异,分析二维及频谱超声各参数测值与NBNA评分的相关性。结果:CHD组胎儿MCAPI,UAPI,CPR,顶枕沟深度,外侧裂深度,距状沟深度与正常组比较差异有统计学意义(P0.05);正常组与16例CHD组新生儿NBNA评分比较差异有统计学意义(P0.05);二维及频谱超声各参数测值与NBNA有一定的相关性(P0.05)。结论:超声不仅能对CHD胎儿心内结构畸形做出明确诊断,还能通过脑沟回及脑血流参数的测量来评估胎脑发育情况,为CHD胎儿转归提供临床依据。     

正常胎儿脑沟超声观察及形态分析

目的观察正常胎儿大脑外侧裂(SF)、顶枕沟(POF)及距状沟(CF)等脑沟的形态发育特点,以及数据的测量,掌握胎儿脑沟回发育的特点。方法收集18~36周的单胎胎儿,记录SF、POF以及CF出现时间,形态特点,并测量SF高度,上缘宽度以及额叶颞叶间未覆盖的最小距离;POF和CF宽度、高度以及顶端角度。结果胎儿孕18周能探及SF,为平滑弧形,在19周后其上缘变平,21周SF几乎均变成梯形。此后,上缘长度随孕周缓慢增加;24周开始上缘两侧逐渐向脑实质内伸展,27周几乎所有胎儿均可见这一表现,此后上缘继续延伸,两脑叶间的未覆盖区逐渐缩小。POF在19~20周左右出现,最晚21周可被探及,在整个孕期宽度前期缓慢上升,后期缓慢下降,23周左右达到最宽,整个孕周高度逐渐增加,夹角逐渐变小。CF的出现较POF略晚,约在20~23周出现,最晚24周可被探及CF。其形态的变化过程与POF类似。结论SF 18周已出现,21周均由弧形转为梯形,25周左右成矩形,27周成“官帽”形。POF 21周最晚出现,26周左右时宽度与高度大致相等。CF最晚24周可被探及,在27~28周时宽度与高度大致相等。各大脑沟深度与孕周增加呈正相关,两脑叶间未覆盖区和顶枕沟角度与孕周增加呈负相关。     

胎儿蛛网膜下腔出血产前超声诊断新方法

目的探讨胎儿蛛网膜下腔出血（SAH）的产前超声诊断策略与方法。 方法以2018年1月至2020年12月南方医科大学附属深圳市妇幼保健院就诊并经超声、磁共振检查确诊的5例SAH胎儿为研究对象,系统分析总结胎儿SAH的产前超声诊断方法及典型特征。 结果5例SAH胎儿产前超声声像图典型表现：（1）大脑外侧裂内均匀高回声5例。（2）额下沟、颞上沟、顶枕沟等表面脑沟回声均匀增强4例。（3）鞍上池、环池、帆间池等脑池内回声均匀增强3例。（4）前、后纵裂,矢状窦,窦汇周围回声增强2例。（5）脊髓圆锥周围蛛网膜下腔增厚强回声1例。（6）SAH出血灶合并颅内其他部位,引起脑实质或脑室内出血4例。（7）大脑中动脉血流峰值流速增高4例。（8）彩色多普勒血流成像显示出血灶内无血流信号5例。 结论胎儿SAH大脑外侧裂有典型均匀高回声表现,是产前超声发现并诊断胎儿SAH的重要线索,继续扫查大脑表面脑沟及脑池等有无均匀高回声表现以及寻找颅内及其他部位有无出血灶,是鉴别SAH有无合并其他颅内出血可靠的诊断思路。     

超声诊断胎儿无脑畸形伴十二指肠狭窄与闭锁1例

孕妇,21岁,孕1产0,孕30周,身体健康,无遗传病史,无不良嗜好,孕期无感染和服药史,来我院行产前三维超声胎儿畸形筛查.超声所见：羊水最大深度15 cm,羊水指数29 cm,内见密集点状强回声,呈＂浑浊＂样回声.胎儿头部横切时不能显示椭圆形的颅骨光环,沿后颈部脊柱方向纵切时,脊柱头侧不能显示颅骨光环和大脑,仅显示颅底部的不均质强回声.胎儿顶合径明显缩短（图1）,面部横切和冠状切面上可见胎儿面部骨结构及眼、鼻、唇、     

三维超声容积对比成像C平面技术评价胎儿小脑蚓部发育的临床研究

目的:应用三维超声容积对比成像C平面(VCI-C)技术量监测胎儿小脑蚓部发育,为胎儿产前筛查提供参考。方法:随机选取450例20-34孕周胎儿,应用三维超声VCI-C技术进行诊断,筛查小脑蚓部发育不良胎儿,并记录胎儿小脑蚓部前后径(AP)、上下径(CC)、周长(C)及最大切面面积(MSA),研究与孕周相关性。结果:450例胎儿中429例超声图像正常,21例图像异常,后经磁共振复查确认小脑蚓发育异常。429例正常胎儿小脑蚓部AP、CC、C、MSA与孕周均呈正相关(r=0.907、0.871、0.932、0.922,均P0.05。结论:容积对比超声成像易于获得清晰显示小脑蚓部所需的正中矢状切面,是有效评估胎儿小脑蚓部发育状况的检查方法     

三维超声扩展成像检测胎儿小脑蚓部发育的研究

目的 应用三维经腹超声检测胎儿小脑蚓部的发育,为产前筛查胎小儿脑蚓部发育异常提供依据.方法 选择于我院行产前超声检查的孕20～36周正常胎儿共387例.应用经腹三维超声扩展成像技术观察胎儿小脑蚓部发育规律,测量蚓部横径、前后径、上下径,上下蚓部面积之比,蚓部与脑干之间的夹角,并分析它们与孕周的关系.结果 应用经腹三维超声扩展成像多切面同屏显示模式和三维重建矢状切面可以评价蚓部形态的完整性和大小,识别蚓部特征性标志:第四脑室顶点和蚓部裂.正常蚓部与脑干之间几乎平行,夹角随着孕周无明显变化,均值为3.97°±1.65°.上下蚓部面积之比随着孕周无明显变化,均值为0.76±0.06.小脑蚓部横径、前后径、上下径均与孕周呈正相关.结论 应用三维扩展成像多切面同屏显示模式和三维重建矢状切面有助于观察小脑蚓部发育情况,显示小脑蚓部与脑干周围关系,为评价胎小儿脑蚓部的发育提供了新的思路.     

经腹超声检测胎儿小脑蚓部及其临床意义

目的 建立不同孕周正常胎儿小脑蚓部的正常值,并探讨其在评估小脑蚓部发育不全中的临床价值.方法 采用经腹超声测量111例20～40孕周正常胎儿小脑蚓部正中矢状面的前后径(AP)和顶尾径(CC).按照上述测值对15例枕大池扩张的胎儿进行评估.结果 ①小脑蚓部AP、CC随孕周(GA)增加而增大(P＜O.05),整个妊娠过程呈线性相关(AP=-5.406+O.761 GA,r=0.97;CC=-5.795+0.783GA,r=0.973);②正中矢状断面小脑蚓部的测值和原裂、次裂、第四脑室顶部的声像图解剖特征有助于确认小脑蚓部发育畸形.结论 经腹超声是确认中晚期妊娠胎儿小脑蚓部发育异常的有效诊断方法.     

三维超声评估胎儿小脑蚓部畸形

目的 探讨经腹三维超声(3D US)检测胎儿小脑蚓部细微结构及诊断蚓部畸形的价值.方法 产前三维超声连续检出的小脑蚓部畸形胎儿28例,按照Barkovich的分类方法诊断,其中4例典型Dandy-Walker畸形(DWM),14例变异型Dandy-Walker畸形(DWV),10例单纯颅后窝池增大(单纯CM).采用经腹3D US观察这些小脑蚓部正中矢状切面上的细微结构,评价其蚓部发育情况,并与相同孕周正常胎儿的声像图、病理进行对照.结果 在3D US正中矢状切面上:(1) DWM胎儿的蚓部缺如或面积极小,与正常胎儿、单纯CM、DWV胎儿比较明显变小(P均＜0.05),原裂、次裂不显示,蚓部分叶不清;(2)DWV胎儿的蚓部面积变小,与正常胎儿及单纯CM胎儿比较明显变小(P均＜0.01),原裂、次裂部分显示不清,蚓部分枝较相同孕周正常胎儿明显减少,第四脑室顶部变浅;(3)单纯CM胎儿的蚓部面积与正常胎儿比较无明显差别(P=0.743),主要结构显示清楚,蚓部分枝与相同孕周正常胎儿无异.结论 在3D US正中矢状切面上观察胎儿小脑蚓部的细微结构和测量蚓部面积有助于鉴别DWM、DWV及单纯CM.     

胎儿小脑表面叶裂的产前超声研究

目的研究正常胎儿小脑表面叶裂随孕周的变化规律并建立孕16~32周正常胎儿小脑叶裂数目参考值。 方法选取2019年6月至2020年12月在南方医科大学附属深圳妇幼保健院行产前超声检查无结构异常的644名妊娠12~32周的单胎孕妇,按孕周分为2个时间段观察：孕12~15周为阶段1,孕16~32周为阶段2,在二维图像上观察原裂、水平裂的显示情况并计数孕16~32周小脑原裂之前、原裂与水平裂之间、水平裂之后的叶裂数目及总数目,并分析其形态变化。随机抽取40名阶段2胎儿行叶裂数目两测量者间的组内相关系数（ICC）分析;建立阶段2胎儿小脑叶裂数目的参考值范围,采用Spearman相关行叶裂数目与孕周的相关性分析并建立拟合方程。 结果叶裂数目的计数两观察者之间的重复性检验一致性较好（ICC=0.969,P＜0.001）。各散点图显示正常胎儿小脑原裂之前、原裂与水平裂之间、水平裂之后叶裂数目及总数目与孕周呈正相关（r=0.863、0.698、0.831、0.932,P均＜0.001）。建立了各区域叶裂数目及总数目与孕周的二次多项式回归方程,原裂之前、原裂与水平裂之间、水平裂之后叶裂数以及总数目与孕周的回归方程分别为：Y=0.974X-0.014X ² -12.65,Y=0.362X-0.005X ² -4.843,Y=-0.125X+0.006X ² +0.285,Y=1.800X-0.024X ² -22.904。 结论利用产前超声可以较好地观察胎儿小脑表面叶裂并对其发育情况作出初步评估。胎儿小脑表面叶裂数目的正常参考值以及形态变化规律能为产前超声评估小脑皮质发育作出参考。     

How early are fetal cerebral sulci visible at prenatal ultrasound and what is the normal pattern of early fetal sulcal development?

OBJECTIVES: To evaluate the time of appearance and pattern of development of fetal cerebral sulci at prenatal ultrasound. METHODS: We studied 50 normal fetuses for visibility of cerebral sulci, especially sulci which appear early in anatomical studies, namely the parieto-occipital fissure, calcarine sulcus, cingulate sulcus, convexity sulci and insula/Sylvian fissure. The gestational ages of the fetuses studied ranged from 15.6 to 29.6 weeks. RESULTS: Sulci could be seen by transabdominal ultrasound as early as 18.5 weeks. Medial hemispheric sulci and the insula were visible earlier and more confidently than convexity sulci. The earliest gestational ages at which specific sulci could be seen in any fetus were as follows: parieto-occipital fissure 18.5 weeks, calcarine sulcus 18.5 weeks, cingulate sulcus 23.2 weeks and convexity sulci 23.2 weeks. In the present series, the gestational ages at which these sulci were always visible were as follows: parieto-occipital fissure >20.5 weeks, calcarine sulcus >21.9 weeks, cingulate sulcus >24.3 weeks and convexity sulci >27.9 weeks. The insula and its margin (the circular sulcus) and the overgrowing opercula undergo characteristic maturation. The circular sulcus at the margin of the insula was initially smooth but started becoming angular after about 17 weeks as it started to be overgrown by the parietal and temporal lobe opercula. Initially the insula/operculum angle was obtuse. An acute angle was first evident at 23.2 weeks and in all fetuses older than 24.5 weeks. Our ultrasound data were consistent with anatomical studies and fetal magnetic resonance imaging findings. CONCLUSIONS: Some cerebral sulci can be seen at prenatal ultrasound as early as 18.5 weeks. Familiarity with the normal pattern of sulcal development and the discriminating gestational ages for the appearance of different sulci may allow early suspicion of lissencephaly.     

Sonographic developmental milestones of the fetal cerebral cortex: a longitudinal study.

OBJECTIVE: To identify sonographic landmarks of normal fetal cortical development. METHODS: Serial ultrasound examinations were performed every 2 weeks from 18 weeks of gestation until term. In each session a detailed examination of the fetal brain was performed and the appearance of the main sulci and gyri was recorded. RESULTS: Twenty-two pregnant women volunteered to participate in the study. The fetal cortex followed an orderly pattern of development. By the time of the first ultrasound examination, at 18 weeks, the major fissures were present. The first sulci could be demonstrated as early as 18 weeks. Main landmarks, represented by the parieto-occipital fissure and the cingulate and calcarine sulci, were present between 22-24 weeks. The central sulcus was present in all cases by 28 weeks. By 30-32 weeks most of the main sulci could be demonstrated. CONCLUSIONS: Prenatal sonographic examinations can accurately demonstrate structures of the fetal cortex. Comparison of our results with those of both magnetic resonance imaging and other sonographic studies shows similarities in the order of appearance of the sulci and gyri, with only minor differences in the exact gestational age at which they are detected. Accurate knowledge of the ultrasound appearance of the fetal cortex at different stages of gestation is important in order to be able to diagnose in-utero malformations of cortical development.     

Prenatal ultrasound findings of lissencephaly associated with Miller-Dieker syndrome and comparison with pre- and postnatal magnetic resonance imaging.

OBJECTIVE: To report on the prenatal ultrasound findings in fetuses with lissencephaly associated with Miller-Dieker syndrome (MDS) and to compare these findings with those of magnetic resonance imaging (MRI). METHODS: Cases of MDS confirmed by postnatal chromosome microdeletion analysis were identified through review of patient records. Prenatal ultrasound scans were reviewed retrospectively by two radiologists. For cerebral cortical development, the Sylvian, parieto-occipital and calcarine fissures, and the cingulate sulcus and sulci over the cerebral convexity were evaluated. If one or more of these fissures or sulci were not visualized at the expected gestational age or their appearance was abnormal for gestational age, cortical development was considered delayed. Prenatal and postnatal MRI examinations were reviewed by a pediatric neuroradiologist. RESULTS: There were seven cases of MDS. In three cases, the prenatal diagnosis of agyria/lissencephaly was prospectively suspected by ultrasound at 23, 26 and 30 weeks, and subsequently confirmed by prenatal MRI. When we retrospectively reviewed the prenatal ultrasound scans of all fetuses, all had delayed cortical development identified on ultrasound performed after 23 weeks' gestation. In all cases the Sylvian fissure was abnormal on both ultrasound and MRI. In one fetus, a normal cortical appearance for gestational age was seen at the initial 20-week ultrasound examination, but delayed cortical development was identified at a 24-week scan. Mild ventriculomegaly was seen in six fetuses and dysgenesis of the corpus callosum in one. Extracranial abnormalities were detected in five fetuses. Delayed cortical development was seen in two fetuses with mild ventriculomegaly, but no other fetal anomalies. CONCLUSIONS: In fetuses with MDS, delayed cortical development can be suspected on ultrasound as early as 23 weeks' gestation. This finding warrants further investigations including MRI and FISH analysis for chromosome 17p13.3 deletion.     

Objective evaluation of sylvian fissure development by multiplanar 3-dimensional ultrasonography.

OBJECTIVE: Evaluation of fetal cerebral cortex sulcation is important for the pre-natal diagnosis of neuronal migration disorders. Although abnormal sylvian fissure morphologic features are frequently observed in these conditions, the diagnosis of an abnormal sylvian fissure relies on subjective interpretation of ultrasonographic images. This study was performed to develop an objective ultrasonographic parameter for sylvian fissure evaluation. METHODS: This cross-sectional study included 202 normal singleton pregnancies without fetal anomalies. Using multiplanar, 3-dimensional ultrasonography, the sylvian fissure midpoint was identified. The sylvian fissure-to-parietal bone distance (SPB) was measured from the midpoint to the inner surface of the parietal bone, perpendicular to the falx cerebri. Bland-Altman plots were used to determine intraobserver and interobserver agreement. Regression analysis was used to evaluate the correlation between SPB measurements and gestational age. RESULTS: Two hundred (99%) of 202 pregnancies had a visible sylvian fissure, identifiable as early as 12 weeks of gestation. The mean SPB values at 12 and 41 weeks were 2.1 and 14.3 mm, respectively. Intraobserver and interobserver mean differences between paired measurements were 0.01 mm (95% limits of agreement, -0.41 to 0.43 mm) and 0.05 mm (95% limits of agreement, -1.79 to 1.90 mm), respectively. A linear correlation was observed between the SPB and gestational age (multiple R=0.91; R2=0.82 [SPB = -2.85 + 0.42 x gestational age]). CONCLUSIONS: (1) The SPB can be reproducibly measured from 12 weeks of gestation to term; and (2) a strong positive correlation was observed between the SPB and gestational age.     

Cerebral asymmetry and the effects of sex and handedness on brain structure: a voxel-based morphometric analysis of 465 normal adult human brains

We used voxel-based morphometry (VBM) to examine human brain asymmetry and the effects of sex and handedness on brain structure in 465 normal adults. We observed significant asymmetry of cerebral grey and white matter in the occipital, frontal, and temporal lobes (petalia), including Heschl's gyrus, planum temporale (PT) and the hippocampal formation. Males demonstrated increased leftward asymmetry within Heschl's gyrus and PT compared to females. There was no significant interaction between asymmetry and handedness and no main effect of handedness. There was a significant main effect of sex on brain morphology, even after accounting for the larger global volumes of grey and white matter in males. Females had increased grey matter volume adjacent to the depths of both central sulci and the left superior temporal sulcus, in right Heschl's gyrus and PT, in right inferior frontal and frontomarginal gyri and in the cingulate gyrus. Females had significantly increased grey matter concentration extensively and relatively symmetrically in the cortical mantle, parahippocampal gyri, and in the banks of the cingulate and calcarine sulci. Males had increased grey matter volume bilaterally in the mesial temporal lobes, entorhinal and perirhinal cortex, and in the anterior lobes of the cerebellum, but no regions of increased grey matter concentration.     

Three‐Dimensional Ultrasonography of the Fetal Vermis at 18 to 26 Weeks' Gestation

Objective. The purpose of this study was to establish the normality of the fetal vermis, ie, the time of appearance of the primary fissure, as well as its measurements between 18 and 26 weeks' gestation, using 3‐dimensional (3D) ultrasonography. Methods. A prospective cross‐sectional study of normal singleton pregnancies was conducted. Examinations were performed with high‐resolution transabdominal ultrasonography using the axial plane in 173 fetuses between 18 and 26 weeks' gestation. Postprocessing measurements of the fetal vermis were done with 4‐dimensional software using static volume contrast imaging and tomographic ultrasound imaging in the C‐plane. Detection of the primary fissure was evaluated in all cases, and the time of appearance was documented. Results. Adequate vermis measurements were obtained in 173 fetuses. Vermian length as a function of gestational age was expressed by regression equations, and the correlation coefficients were found to be highly statistically significant (P < .001). The normal mean ± 2 SD for each gestational week was defined. The primary fissure was observed at 24 weeks' gestation in all cases, at 22 weeks in 94% of cases, and as early as 18 weeks in 40%. Conclusions. This 3D study documents the appearance of the primary fissure and presents the normal range of vermian measurements, confirming normal development of the fetal vermis starting as early as 18 weeks' gestation. It also shows an easy method for visualizing the vermis with 3D ultrasonography at every gestational week regardless of fetal presentation.